Reference
Fast vs Best Quality
The background remover offers two modes, and the right one depends entirely on your subject’s edge. Here is what actually differs between them and a one-line rule for picking.
| Fast | Best Quality | |
|---|---|---|
| What it does best | Hard-edged subjects — products, logos, graphics | Soft edges — hair, fur, feathers, motion blur |
| Edge handling | Crisp yes/no mask (segmentation) | Partial transparency along edges (matting) |
| Speed | Fastest — often a second or two | Slower — a heavier model, more work per edge |
| Runs on | Any modern browser (CPU/WASM) | GPU (WebGPU) when available, CPU fallback |
| First-use download | Small, cached after first run | Larger one-time download, then cached |
Fast — a crisp yes/no mask
Fast mode runs a lightweight model that answers one question per pixel: subject, or not subject. That produces a clean, decisive edge and it does it quickly, on essentially any device, with only a small model to download the first time. For anything with a definite manufactured boundary — a bottle, a phone, a packaged product, a logo, a screenshot — this is the right tool, and reaching for the heavier mode buys you nothing but a longer wait.
Best Quality — soft edges done properly
Best Quality runs a heavier model that estimates how much of each edge pixel belongs to the subject, rather than forcing every pixel to fully-in or fully-out. That distinction — segmentation versus matting — is exactly what a windblown ponytail, a fur collar, or a fern needs. The cost is real: it is a bigger model and more computation per edge, so it takes longer and prefers a GPU.
Why Best Quality prefers a GPU (and what happens without one)
When your browser supports WebGPU, Best Quality runs on the GPU for speed. When it does not — older browsers, certain drivers — it automatically falls back to the CPU path, which is slower but produces the same result. We also added a safety check: if the GPU path ever returns a suspiciously empty mask, the tool re-runs the image once on the CPU before trusting it, so a backend hiccup can no longer hand you a blank cutout. The background on why that fallback exists is in how Best Quality uses WebGPU with a WASM safety net.
Downloads and privacy
Both models download to your device the first time you use them and are cached afterwards, so the wait is a one-time cost per browser. Best Quality’s model is the larger of the two. Crucially, the models come to your device — your images never leave it. Every removal happens locally, which is why there is no upload step and no account.
The simple rule
Hard edge → Fast. Soft edge → Best Quality. If your subject has a clean manufactured outline, Fast will nail it in a second. If it has hair, fur, feathers, or motion blur, spend the extra seconds on Best Quality. When a result still looks wrong, the troubleshooting guide walks through the fixes symptom by symptom.