Here's the thing nobody tells you upfront: these two chips make completely different trade offs, and which one is "faster" depends entirely on what you actually do with your laptop. The M4 demolishes the Snapdragon in single core work and GPU tasks. The Snapdragon hits back with a beefier NPU and aggressive multi core scaling when all 12 cores are loaded. Battery life? Apple still leads, but not by the canyon wide margin you'd expect. I've been tracking this matchup since both chips launched, and I'm going to break down every angle, raw CPU numbers, GPU rendering, AI workloads, app compatibility headaches, and real battery drain, so you can stop guessing and start buying.

Single Core CPU: The M4 Still Runs Away With It

But "impressive for a first attempt" and "competitive with Apple's fourth-generation silicon" are two very different statements. If your workflow is dominated by single-threaded tasks, think Photoshop filters, Excel macros, web browsing with 40 tabs, the M4 is the chip you want. Full stop.

This one isn't close. Not even a little. The Apple M4 posts a Geekbench 6 single core score around 3,698 on the MacBook Air, while the Snapdragon X Elite lands between 2,575 and 2,780 depending on the variant and cooling. That's roughly a 35-45% lead for Apple on the workloads that matter most for everyday use, opening apps, compiling a quick script, rendering a webpage. The M4's performance cores clock up to 4.4 GHz on Apple's 3nm TSMC process, and they're wider cores that chew through instructions faster per cycle. Qualcomm's Oryon cores are impressive for a first generation, sure. But "impressive for a first attempt" and "competitive with Apple's fourth generation silicon" are two very different statements. If your workflow is dominated by single threaded tasks, think Photoshop filters, Excel macros, web browsing with 40 tabs, the M4 is the chip you want. Full stop.

Multi Core Performance: Closer Than You'd Think

Here's where Qualcomm claws back some dignity. The Snapdragon X Elite packs 12 performance cores (no efficiency cores at all), and in Cinebench 2024 multi core tests it actually edges out the base M4 by about 13%. The M4's Geekbench 6 multi core sits around 14,753 on the Air, while the top X Elite variant hits roughly 14,078, a narrow Apple lead in that benchmark, but flip to Cinebench and the story reverses. Why the inconsistency? Different benchmarks stress different things. Cinebench hammers sustained all core loads like video rendering, and having 12 real performance cores versus the M4's 6 performance + 4 efficiency layout pays off there. For content creators doing long Blender renders or heavy code compilation, the X Elite's brute force core count is genuinely useful. It's not a knockout, though. More like a split decision.

GPU Performance: Apple's Quiet Domination

Graphics is where Apple pulls ahead dramatically and nobody talks about it enough. The M4's 10 core GPU scores around 54,684 in Geekbench GPU tests, while the Adreno X1 inside the Snapdragon X Elite trails by roughly 40-50% in most synthetic benchmarks. In 3DMark Wild Life Extreme, the M4 delivers about 51% faster graphics output. That translates directly to smoother performance in Final Cut Pro, DaVinci Resolve timelines, and even casual gaming. The Adreno X1 isn't terrible, it handles light creative work and older titles fine, but if you're doing any kind of GPU accelerated work, the M4 is in a different league. Apple's tight hardware software integration means Metal API optimizations squeeze every drop out of that silicon. Qualcomm's GPU drivers for Windows, meanwhile, have improved a lot since launch but still occasionally stutter in ways that remind you this ecosystem is young.

AI and NPU: Qualcomm's One Clear Win

The Snapdragon X Elite's Hexagon NPU delivers 45 TOPS of on device AI performance. Apple's M4 Neural Engine? 38 TOPS. That's a meaningful 18% advantage for Qualcomm in raw neural processing throughput, and it matters more in 2026 than it did at launch. Windows Copilot features, local Stable Diffusion inference, real time transcription, background noise removal in Teams calls, these all lean on the NPU. Microsoft has been shipping Copilot Plus features that are exclusive to Snapdragon powered PCs (at least initially), giving X Elite users access to Recall, Live Captions translation, and Cocreator in Paint before Intel or AMD machines get them. Apple has its own Neural Engine tricks in macOS, of course, but the M4's AI story is more about developer frameworks than raw TOPS. Important context: Qualcomm's next gen X2 Elite bumps to 80 TOPS, which makes the current gap look like a preview of a much wider one.

Battery Life: Apple Leads, But the Gap Has Shrunk

I expected the M4 MacBook Air to obliterate the Surface Laptop 7 in battery life. It didn't. Well, it won, but not by the embarrassing margin I anticipated. The MacBook Air M4 hits about 15-17 hours of mixed real world use and pushes past 20 hours in video playback. The Surface Laptop 7 with X Elite manages around 13-15 hours for similar tasks. That's a solid 2-3 hour Apple advantage, which matters, but it's not the 5-6 hour chasm that separated Intel Windows laptops from MacBooks a few years ago. Apple's 3nm process gives it a fundamental efficiency edge, the M4 draws roughly four times less power at max load compared to the X Elite, which is wild. But during lighter tasks like web browsing and document editing, both chips sip power conservatively enough that you'll get through a full workday on either one. The real difference shows up during sustained heavy workloads. Push both chips hard for two hours straight and the MacBook stays cool while the Surface gets noticeably warm.

App Compatibility: The Elephant in the Room

This used to be a dealbreaker. Honestly? It's mostly not anymore. As of early 2026, the Prism emulation layer on Windows 11 ARM handles the vast majority of x86 applications without you even noticing. Chrome, Slack, Zoom, Office, Adobe Creative Suite, VS Code, all either native ARM builds or running flawlessly through emulation. The caveat: emulated apps take a 10-30% performance hit compared to native execution, and they use more RAM and battery. Certain niche tools, specific audio production plugins, older enterprise software, some anti cheat systems in games, still break or refuse to install. Gaming remains the biggest weak spot; most AAA titles either don't run or run poorly through emulation, though this is improving as engines ship ARM native builds. On the Mac side, the Rosetta 2 translation layer is more mature and generally faster, but macOS has its own app gaps, no native AutoCAD, limited enterprise software support, and the eternal "but can it run my company's weird internal tool" question. Neither platform is perfect. But for 90% of mainstream users, both work fine.

Pricing and Value: Where Your Dollar Goes Further

Here's where things get interesting for budget conscious buyers. The Surface Laptop 7 with Snapdragon X Elite has been dropping in price aggressively, clearance deals have pushed it as low as $699, and the standard config with 16GB RAM sits around $1,049. The MacBook Air M4 starts at $1,099 for the base 16GB model and rarely sees meaningful discounts. The Dell XPS 13 with X Elite has dipped to $999 at times. Dollar for dollar, you're getting more hardware on the Windows side right now, especially since Microsoft is clearing inventory ahead of X2 Elite machines. But "cheaper" doesn't mean "better value" if you're locked into the Apple ecosystem, iMessage, AirDrop, Handoff, and the seamless iPhone to Mac pipeline are worth real money to people who use them daily. If you're ecosystem agnostic, though, the Snapdragon X Elite laptops represent genuinely strong value at current street prices.

Which Snapdragon X Elite vs Apple M4 Laptop Chip Should You Actually Pick?

Forget the spec sheets for a second. If you edit video, do creative work, or want the best single core speed and GPU grunt in a fanless ultrabook, buy the MacBook Air M4. Not close. If you need Windows specifically, for enterprise software, gaming potential, or because your workflow demands it, the Snapdragon X Elite is finally a Windows ARM chip that doesn't feel like a compromise. The NPU advantage matters if you're leaning into AI powered workflows. Battery life favors Apple but not by enough to swing the decision alone. And if you're patient, the Snapdragon X2 Elite arriving in Q2 2026 promises to close the CPU and GPU gaps substantially while doubling NPU performance to 80 TOPS. My honest take: both are excellent chips that have made Intel's current laptop lineup look sluggish. You're choosing between two genuinely good options, and that's the real story of the Snapdragon X Elite vs Apple M4 laptop chip battle in 2026.

Do’s and Don’ts

Picking between these two chips gets a lot easier once you know which claims to trust and which to ignore. The table below distills the benchmarks and real world testing from this comparison into quick rules you can apply while you shop. Run through it before you click buy on either machine.

FAQs

Is the Snapdragon X Elite faster than the Apple M4 in real world use?

It depends entirely on the task. For single core workloads like web browsing, app launching, and light photo editing, the Apple M4 is roughly 35-45% faster based on Geekbench 6 scores, the M4 hits around 3,698 single core while the X Elite lands near 2,700. In multi core tasks like video rendering and code compilation, they're much closer, with the X Elite's 12 core design occasionally pulling ahead by 10-13% in Cinebench. For GPU heavy work, the M4 wins by 40-50%. So "faster" really means "faster at what," and for most mainstream laptop tasks, the M4 has the edge.

How does battery life compare between Snapdragon X Elite and Apple M4 laptops?

The MacBook Air M4 consistently delivers 15-17 hours of mixed real world use, stretching past 20 hours for video playback. Snapdragon X Elite laptops like the Surface Laptop 7 manage around 13-15 hours for similar tasks. That's a 2-3 hour gap favoring Apple, driven largely by the M4's 3nm process drawing significantly less power under load. During light tasks like document editing, both platforms last a full workday comfortably, but the difference becomes obvious during sustained heavy workloads where the M4's efficiency advantage really compounds.

Can I run all my Windows apps on a Snapdragon X Elite laptop?

Almost all of them, yes. The Prism emulation layer in Windows 11 ARM has matured significantly through 2025 and into 2026. Major apps like Chrome, Office, Adobe Creative Suite, VS Code, Slack, and Zoom all run natively or through seamless emulation. The trouble spots are niche: certain audio plugins, older 32 bit enterprise tools, some anti cheat software for games, and specific hardware drivers. Emulated apps do take a 10-30% performance hit compared to native execution. I'd recommend checking windowsonarm.org for a compatibility list of your specific tools before buying.

Which chip is better for AI and machine learning tasks?

The Snapdragon X Elite has the stronger NPU at 45 TOPS versus the M4's 38 TOPS, giving it an 18% advantage in raw neural processing. This matters for on device AI features like Windows Copilot, local image generation, and real time transcription. However, Apple's Neural Engine is better optimized for Core ML frameworks, and many AI developer tools like PyTorch and TensorFlow have deeper macOS integration. If you're using AI as a consumer through built in OS features, the Snapdragon's NPU edge is meaningful. If you're developing ML models, the M4's broader software ecosystem often matters more than raw TOPS.

Should I wait for the Snapdragon X2 Elite instead of buying now?

If you can wait until Q2 2026, probably yes. Early benchmarks of the X2 Elite Extreme show it matching or beating the M4 Pro in single core performance, a massive leap from the first generation. It also jumps to 80 TOPS on the NPU (doubling the current gen) and adds the Adreno X2-90 GPU. The 18 core variant scored 3,807 single core in Geekbench 6, which would essentially close the gap with Apple's M4. However, first gen X Elite laptops at clearance prices ($699-999) represent excellent value right now if you need a laptop today and can live with current performance levels.

Is the Snapdragon X Elite good enough for creative professionals?

For light to moderate creative work, photo editing in Lightroom, web design, illustration, absolutely. The X Elite handles these tasks well, especially with native ARM versions of Adobe apps now available. For heavy creative workflows like 4K video editing, 3D rendering, or color grading in DaVinci Resolve, the M4's significantly faster GPU becomes hard to ignore. The Adreno X1 trails the M4's GPU by 40-50% in benchmarks, and that gap translates to real world timeline scrubbing speed and export times. If creative work is your primary use case and you're not locked into Windows, the MacBook Air M4 or MacBook Pro M4 Pro is the stronger choice.

How do the Snapdragon X Elite and Apple M4 compare on thermals and fan noise?

The MacBook Air M4 is fanless and stays remarkably cool during normal use, Apple's 3nm process generates less heat per watt, so it rarely throttles during everyday tasks. Push it hard with a long export and it will thermal throttle, since there's no fan to dissipate heat. The Surface Laptop 7 with X Elite has a fan that kicks in under load, which means it can sustain peak performance longer during intensive tasks but generates audible noise. Under light workloads both stay silent and cool. The M4 draws roughly four times less power at max load, which is why it can get away with passive cooling in the first place.

Are Snapdragon X Elite laptops cheaper than MacBooks with M4?

Right now, significantly so. The Surface Laptop 7 with X Elite has hit clearance prices as low as $699, and well configured models with 16GB RAM regularly sell for $1,049. The Dell XPS 13 with X Elite has been spotted at $999. Compare that to the MacBook Air M4 starting at $1,099 with Apple's historically stingy discounts, and you're looking at a $100-400 price gap favoring Windows ARM. That said, MacBooks hold resale value far better, a two year old MacBook Air sells for 60-70% of its original price, while Windows laptops typically lose 50% or more in the same period.

I've spent weeks swapping between them as daily drivers, a dozen Chrome tabs, Slack, VS Code, Spotify humming in the background, the occasional Lightroom session when I pretend I'm a photographer. Both handled it without flinching, which makes this comparison trickier than most. The real gaps show up in display quality, battery consistency, pricing tiers, and ecosystem lock in. Each laptop wins in different categories depending on what you prioritize, and I'll break down exactly where so you can stop overthinking this and just buy one already.

MacBook Air M4 vs Dell XPS 14: Raw Performance

The M4 posts a Geekbench 6 single core score of 3,698 and multi core of 14,753. Impressive for a fanless $999 machine. The XPS 14 with Intel's Core Ultra X7 358H hits 2,867 single core and 16,927 multi core. Apple wins single threaded work by roughly 29%, while Dell claws back a 15% lead in multi threaded tasks. In practice? The MacBook Air feels snappier for everyday use, apps launch faster, tabs render quicker, responsiveness feels tighter. But batch exports in Premiere or heavy code compilation favor the XPS 14's extra thread throughput. Neither laptop will bottleneck a typical knowledge worker.

Display: Liquid Retina vs Tandem OLED

Not close. The MacBook Air's 13.6 inch Liquid Retina at 2560×1664 and 500 nits looks great for IPS. Clean, color accurate, perfectly fine. But Dell's optional tandem OLED at 2880×1800 is a different league entirely, the same stacked OLED tech Apple uses in the iPad Pro M5, delivering true blacks and infinite contrast. I pulled up the same RAW photo on both screens side by side. The OLED made the Retina look like it had a thin film over it. One caveat: Dell also sells a cheaper 1920×1200 IPS version that's noticeably worse than Apple's panel. Compare the right configs.

Battery Life: A Complicated Story

Apple claims 18 hours for the MacBook Air M4. Real world mixed use gives me 12-14 hours. Excellent for a 2.7 pound laptop. The XPS 14 tells a wilder story. The IPS model with Core Ultra 5 allegedly hits 22+ hours. The OLED with Core Ultra X7? Closer to 8-10 hours in my testing. That's a massive config gap. Honest take: buy the base XPS 14 LCD and you'll outlast the MacBook Air all day. Buy the OLED, the one you actually want, and battery life is comparable or slightly worse. Apple's M4 unified memory architecture still wins on sustained efficiency.

Build, Weight, and the Keyboard Situation

MacBook Air M4: 2.7 pounds, 11.3mm thin, aluminum unibody. Rock solid. The XPS 14: 3.0 pounds for OLED, 14.6mm thick, machined aluminum and glass. Both feel premium. But I need to address Dell's keyboard. The zero lattice design looks futuristic, keycaps flush against each other, no gaps. Early units had a documented issue where fast typists missed keystrokes. Dell acknowledged it and says current units have the fix. The MacBook Air's keyboard? Just reliably good. Great travel, consistent feel, zero drama. Sometimes boring is exactly what you want.

Pricing: Where Apple Finally Competes

MacBook Air M4: $999 base (16GB/256GB), $1,199 for 512GB storage, $1,499 for 24GB/1TB. The XPS 14 starts at $1,599 for IPS with Core Ultra 5. OLED with Core Ultra X7 runs $2,199 as reviewed. That's a $600-900 gap. A fully loaded MacBook Air costs less than a mid tier XPS 14. Wild. Dell's OLED and Panther Lake are impressive, but the premium is real. If budget matters, and it should, the MacBook Air M4 wins on value by a significant margin.

Who Should Buy Which, The MacBook Air M4 vs Dell XPS 14 Verdict

Grab the MacBook Air M4 if you want the best value ultrabook available. Period. $999 for a fanless machine with 16GB RAM, an M4 chip beating most Intel laptops in single core, and 12-14 hours of real battery is absurd. Pick the Dell XPS 14 if you need Windows, want the best ultrabook display money can buy, or need multi core muscle from Panther Lake. Just know you're spending $1,599-$2,199 for the privilege. Both are genuinely excellent. You won't regret either one.

Do’s and Don’ts

Most buyer's remorse in this matchup comes from small decisions made at checkout, not from picking the wrong brand. Storage tiers, display options, and warranty coverage move the real cost far more than the sticker price suggests. Keep these habits in mind before you put either laptop in your cart.

FAQs

Is the MacBook Air M4 faster than the Dell XPS 14 2026?

Depends on the workload. The MacBook Air M4 scores 3,698 in Geekbench 6 single core versus the XPS 14's 2,867, a 29% advantage that translates to snappier app launches and smoother everyday interactions. The Dell pulls ahead in multi core at 16,927 vs 14,753, which matters for video editing and code compilation. For standard productivity, the MacBook Air feels faster day to day.

Which laptop has better battery life?

The MacBook Air M4 consistently delivers 12-14 hours of real mixed usage. The Dell XPS 14 varies wildly by config, the IPS model can last 22+ hours, but the OLED model drops to 8-10 hours. If you're buying the OLED XPS 14, expect battery life roughly on par with or slightly below the MacBook Air.

Is the Dell XPS 14 OLED display worth the extra cost?

For color critical work like photo editing or video grading, absolutely. The tandem OLED delivers true blacks and infinite contrast that the MacBook Air's IPS panel can't match. For everyday web browsing and documents, you probably won't notice enough difference to justify a $600+ premium. Stunning, but a luxury for most buyers.

Can I game on either laptop?

Neither is a gaming laptop, but the XPS 14 handles it better. Steam's full library runs on Windows, while Mac is limited to a smaller catalog of native titles. The MacBook Air is fanless, so sustained gaming throttles performance after 15-20 minutes. The XPS 14 has active cooling and maintains higher GPU clocks longer. For casual gaming, either works. For serious gaming, neither works, buy a desktop.

Does the Dell XPS 14 2026 keyboard problem still exist?

Dell acknowledged "a small batch of early units" shipped with keystroke recognition issues and says it's resolved in current production. Later production reviewers confirmed improved key registration. Buying new from Dell directly should be fine. Third party sellers or used units, verify the manufacturing date.

MacBook Air M4 vs Dell XPS 14, which is better for students?

The MacBook Air M4 at $999. Lighter at 2.7 pounds, cheaper by $600+, consistently great battery life for all day classes. The only exception: coursework requiring Windows specific software like certain engineering or accounting tools. For 90% of students, the MacBook Air is the better buy. No contest.

This MacBook Air M4 review covers the real numbers, benchmark scores, actual battery life, display strengths and weaknesses, and whether jumping from an M2 or M3 makes financial sense. I've also compared it against Windows ultrabooks in the same price bracket, because specs without context are just marketing. I'm not sponsored, I don't get affiliate bumps, and I'll flag the genuine frustrations alongside the wins. Fair warning: there are a few.

MacBook Air M4 Review: What Changed Under the Hood

The chassis is identical to the M3 Air, same 0.44 inch profile, same weight, same port layout. Cynics will call it a spec bump. They're half right. The M4 chip runs a 10 core CPU (four performance, six efficiency) versus the M3's eight cores total. Geekbench 6 scores land around 3,622 single core and 14,223 multi core, roughly 25% and 30% improvements respectively. The GPU picks up a 21% bump you'll notice in Lightroom and Final Cut. Apple also finally made 16GB RAM the baseline. The 8GB config on a $1,099 laptop in 2024 was frankly embarrassing. Fixed now. Other upgrades: Thunderbolt 4 ports replace Thunderbolt 3, a 12MP Center Stage webcam replaces the old 1080p camera, and the Air now drives two external 6K displays with the lid open. That last one matters if you work at a desk.

Battery Life That Borders on Absurd

Tom's Hardware measured 15 hours and 14 minutes on their standardized test, web browsing, video streaming, light OpenGL at 150 nits. Borderline silly. My real world experience: 13-14 hours of mixed use with browsing, Docs, Spotify, and some Lightroom. A friend who sticks to email and Notion regularly finishes a full workday with 40% remaining. Forty percent. Most Windows ultrabooks in this bracket consider 8-10 hours "solid." The M4 Air nearly doubles that. Here's the technical reason: despite higher benchmark scores, the M4 chip spends more time in a zero frequency idle state than the M3 did. It works harder, finishes faster, then sleeps deeper. Clever engineering.

Display: Beautiful but Frustratingly 60Hz

The 13.6 inch Liquid Retina panel runs at 2560×1664, 224 PPI, 500 nits, with P3 wide color gamut and True Tone. Photos look stunning. Video playback is excellent. But it's still 60Hz in 2026. The MacBook Pro moved to 120Hz ProMotion years ago, and the difference is obvious during fast scrolling, text smears slightly on the Air while the Pro stays butter smooth. If you've used any modern 120Hz phone (basically everyone), you'll notice. Also missing: nano texture display option. Apple offers it on the Pro to cut glare, but Air buyers get the standard glossy panel. Working near a window means playing the angle adjustment game.

Who Should Buy It, and Who Shouldn't

Perfect for: students, writers, web developers, business professionals, and anyone whose heaviest task is browser tabs plus Slack plus a creative app. The M4 handles all of that without breaking a sweat or making a sound. Skip it if you edit long 4K timelines regularly, the fanless design throttles during sustained exports. Gamers should look elsewhere too; macOS gaming improved but the library still can't match Windows, and the 10 core GPU won't push demanding titles. You also get just two USB C ports. No HDMI, no SD slot, no USB A. If you regularly plug in multiple peripherals without a dock, that's a genuine daily friction point.

MacBook Air M4 Review: Pricing and the Right Config

The 13 inch starts at $999 (16GB/256GB). The 15 inch starts at $1,199 with identical internals. My advice: skip the 256GB storage. Terrible value. macOS alone eats 30GB+, and you'll burn through the rest fast. The 512GB upgrade costs $200, putting the 13 inch at $1,199, that's the sweet spot. The 24GB RAM option ($200 more) makes sense for developers running Docker or people with 40+ tab habits. For everyone else, 16GB is genuinely comfortable. Don't touch the 32GB, Apple charges $400 total for that jump, and few people outside professional workflows will use it. Pick the 13 inch for portability, the 15 inch if it mostly lives on a desk without an external monitor.

M4 vs M3 Air: Is Upgrading Worth It?

Straight answer: if you own an M3 Air, probably not. The 25-30% performance bump is real but invisible in everyday tasks like browsing and writing. You won't feel it. The meaningful upgrades are 16GB base RAM (only matters if you bought the 8GB M3), the better webcam, Thunderbolt 4, and dual display support. Coming from an M1? Stronger case, two generations of improvements add up, and the RAM jump from 8GB to 16GB baseline is noticeable with modern app memory demands. From an Intel Mac? Just buy it. Seriously. The difference feels like a completely different product category.

Do’s and Don’ts

Months of daily use taught me which configuration choices pay off and which ones quietly waste money. This table pulls those lessons together in one place. Give it a scan before you hit the buy button, especially the storage and RAM rows.

FAQs

These are the questions I keep getting from readers weighing up the M4 Air. Short, honest answers follow.

Is the MacBook Air M4 worth buying in 2026?

At $999 for a 10 core CPU, 16GB unified memory, a Liquid Retina display, and 15+ hours of battery life, nothing in the Windows space matches this value. The build quality is excellent, macOS runs smoothly on Apple silicon, and the machine should comfortably last 5+ years. The only people who shouldn't buy it are those already on an M3 Air, wait for the M5 instead.

How long does MacBook Air M4 battery actually last?

Tom's Hardware measured 15 hours 14 minutes in standardized testing. Real world mixed usage (browsing, documents, music, light editing) gives me 13-14 hours consistently. Light users push past 15. Heavy video calls or compilation work drops it to 8-10 hours, which is still better than most Windows competitors at this price.

Can the MacBook Air M4 handle video editing?

Casual to moderate, yes. I've edited 4K clips in Final Cut and DaVinci Resolve without issues on short projects, YouTube videos, social clips, family footage. Long 4K exports (20+ minutes of timeline) cause thermal throttling since there's no fan. For heavy video work, spring for the MacBook Pro.

Is 16GB RAM enough on the MacBook Air M4?

For most people, absolutely. Apple's unified memory architecture stretches further than traditional RAM. I run Safari with 25+ tabs, Slack, Spotify, and VS Code simultaneously without memory pressure. Step up to 24GB only if you use Docker, VMs, or work with large datasets regularly.

Should I get the 13 inch or 15 inch MacBook Air M4?

The 15 inch costs $200 more and gives you a bigger display, slightly louder speakers, and better battery. Internals are identical. Get the 15 inch if it mostly sits on a desk without an external monitor, the extra screen real estate helps with side by side windows. Get the 13 inch if you carry it everywhere.

Does the MacBook Air M4 support two external monitors?

Yes, a genuine upgrade over the M3. It drives two 6K displays with the lid open, or one 6K display with the lid closed. The M3 was limited to a single external monitor without workarounds. If you have a dual monitor desk setup, this alone might justify upgrading.