WebP Compressor — Reduce WebP Size Online
Compress WebP images in your browser. Choose quality, see before/after sizes. Transparency preserved automatically. Files stay on your device.
Why compress WebP?
WebP is already small — that's the point of the format — but it's not automatically as small as it could be. Tools and apps that export WebP often use conservative quality defaults (95–100). Dropping to 80–85 typically cuts another 40–60% off the file size with no visible quality loss, making your already-modern images even faster to load.
Page weight directly affects Largest Contentful Paint (LCP), one of the three Core Web Vitals that Google factors into search ranking. Heavier images mean slower LCP, lower rankings, lower conversion rates, higher bounce rates. Compressing WebP is one of the cheapest wins available for both SEO and user experience.
How this compressor works
The browser decodes your WebP into a hidden canvas, optionally resizes it, and re-encodes it as a new WebP at your chosen quality. The encoder is your browser's native WebP implementation (libwebp under the hood), so output quality matches what you'd get from Squoosh, Google's reference WebP tool. Transparency is preserved automatically — WebP's full 8-bit alpha channel survives the round-trip.
Quality settings — what each range gives you
- 95–100 — near-lossless. File 15–30% smaller than the source. Archival quality.
- 85–95 — visually identical for most photos. 40–60% smaller. Use for hero images.
- 75–85 — the sweet spot. 60–75% smaller. No visible loss on photographs.
- 60–75 — visible only on close inspection. Great for thumbnails.
- Below 60 — obvious artefacts on detailed images. Use for very small previews.
Bonus saving: resize + compress
If your WebP is much larger than its display size, resizing it down to the target size first then compressing gives dramatically smaller files. Untick "Keep original dimensions" and pull the max-width slider to your display size. A typical hero image at 1920 pixels wide for desktops needs that resolution — but a thumbnail in a card grid only needs 600 pixels. Sizing appropriately can cut total weight by another 75% on top of the quality savings.
Tips and best practice
- Don't repeatedly compress WebP. Each lossy pass adds artefacts on top of previous artefacts. Compress once from the highest-quality source you have.
- Use the original source format (PNG, RAW) when available for the cleanest compression target.
- Pick 80 as your default quality. If photos look soft, try 85; if file size matters more, try 70.
- Compress before deploying to production. Don't rely on the CMS or CDN to do it; they're often configured conservatively.
- For hero/above-the-fold images, serve a smaller (well-compressed) variant for mobile and the full version for desktop using
<picture>.
FAQs
Will transparency be preserved?
Yes. WebP's alpha channel is preserved by the canvas re-encode.
Is anything uploaded?
No. Everything runs in your browser.
Why is my compressed WebP nearly the same size?
Your source was probably already heavily compressed. Try compressing from the original PNG or JPG instead.
What's the maximum file size?
Soft 50 MB. Browser memory is the real limit.
Does this strip metadata?
Yes. The canvas re-encode drops EXIF and other metadata — a privacy plus.