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.