WebGL Build Size Estimator
Get a ballpark estimate of your Unity WebGL build size and load time based on your project’s scope and compression settings. For the full optimization walkthrough, see our WebGL optimization guide.
Step 1 — Project size
Step 2 — Compression format (Player Settings → Publishing Settings)
Your estimate will appear here once you pick a project size and a compression format.
Almost there — now pick a compression format.
Almost there — now pick a project size.
Estimated build size: 8 – 15 MB
Estimated load time: ~3 – 6 seconds on typical broadband
You’re already in a great spot. Keep texture sizes at 1024px or below and avoid uncompressed audio to stay this lean.
Estimated build size: 10 – 18 MB
Estimated load time: ~4 – 8 seconds on typical broadband
Perfectly fine for a demo. If you host over HTTPS anyway, switching to Brotli shaves another 15–20% for free.
Estimated build size: 20 – 35 MB
Estimated load time: ~10 – 18 seconds on typical broadband
Enable Brotli (or at least Gzip) under Publishing Settings. It’s the single biggest free file-size reduction available — no code changes required.
Estimated build size: 25 – 45 MB
Estimated load time: ~10 – 20 seconds on typical broadband
Compression is handled — now audit textures. Switch to Crunch or ASTC compression, and hunt for any 4K textures that don’t need to be that large.
Estimated build size: 30 – 55 MB
Estimated load time: ~12 – 25 seconds on typical broadband
Borderline for player patience. Move to Brotli if your host supports HTTPS, then tackle texture import settings and audio bitrates.
Estimated build size: 60 – 100 MB
Estimated load time: ~30 – 60 seconds on typical broadband
This is the danger zone for player drop-off. Enable Brotli immediately, and consider Addressables to load scenes on demand instead of bundling everything upfront.
Estimated build size: 60 – 120 MB
Estimated load time: ~30 – 60 seconds on typical broadband
Use Addressables or AssetBundles to split your build so players start playing before everything downloads. A loading-screen build isn’t the same as a fast build.
Estimated build size: 75 – 150 MB
Estimated load time: ~40 – 75 seconds on typical broadband
Switch to Brotli for a quick win, but the real fix is structural: Addressables for on-demand content, Vorbis audio at a lower bitrate, and a texture max-size audit.
Estimated build size: 150 – 300+ MB
Estimated load time: 2+ minutes — many players will simply leave
This build needs real surgery: enable Brotli, split content with Addressables, compress audio to Vorbis at a lower bitrate, and re-check every texture’s max size.
Rough, illustrative estimates based on typical Unity WebGL projects, assuming a ~25 Mbps connection — not a guarantee for your specific build. Always check the real number in Build Profiles → Build, and remember the browser must also decompress and compile the WebAssembly before play starts.
📦 Build size is only half the story
Once the download is lean, draw calls decide how smoothly the game runs in a browser. Mesh Baker combines meshes and atlases materials to cut them, and it’s one of the Asset Store tools we think is worth buying.