Image compressor & optimizer
Shrink JPG, PNG, and WebP images without losing visible quality - convert formats, set a target size, and batch download. Runs entirely in your browser.
Settings
WebP is smallest for the web. PNG keeps transparency (quality slider ignored).
Downscale wide images. Leave blank to keep original size.
Your images are compressed locally and never uploaded to any server.
Is a slow, heavy site costing you customers?
Oversized images are the #1 cause of poor Core Web Vitals. We build fast, modern sites with images optimized from the start.
Talk to an engineerQuick answer: An image compressor reduces an image's file size - by lowering quality, resizing dimensions, or converting to an efficient format like WebP or AVIF - while keeping it visually sharp. Smaller images load faster, improve Core Web Vitals, and cut bandwidth. This tool compresses entirely in your browser, so your files are never uploaded.
Image format comparison
| Format | Best for | Transparency | Relative size |
|---|---|---|---|
| JPEG | Photos, wide compatibility | No | Baseline |
| PNG | Logos, screenshots, line art | Yes | Largest (lossless) |
| WebP | Modern websites (best default) | Yes | ~25-35% smaller than JPEG |
| AVIF | Cutting-edge web, max savings | Yes | Smallest, slower to encode |
For most websites in 2026, WebP is the best balance of file size, quality, and browser support. AVIF saves even more but encodes slower and isn't supported everywhere.
How image size affects SEO & Core Web Vitals
Images are usually the heaviest thing on a page, so they're the biggest lever on load time. A hero image that's 3 MB instead of 200 KB can single-handedly wreck your Largest Contentful Paint (LCP) - the Core Web Vital that measures when the main content appears. Because Google uses Core Web Vitals as a ranking signal and slow pages drive higher bounce rates, compressing images and serving modern formats is one of the highest-impact, lowest-effort performance wins available. Pair compression with correct dimensions (don't ship a 4000px image into a 800px slot) and lazy loading for the biggest gains.
How to compress to a target size (e.g. 100 KB)
Turn on "Compress to a target size" and enter your limit in KB. The tool searches for the highest quality setting that still lands at or under your target, so you get the best-looking image within the size budget. If the target is very small, also set a max width to downscale the image first - reducing dimensions cuts file size faster than quality alone.
How to compress an image (step by step)
- Add your images - drag and drop or select up to 20 files.
- Choose a format - WebP for the smallest web files, or keep the original.
- Set quality or a target size - use the slider, or hit an exact KB limit.
- Download - grab each file, or all of them as a ZIP.
Frequently asked questions
- Does compression reduce quality?
- Lossy formats discard some data, but quality around 75-85% removes most file size with little visible difference. PNG is lossless.
- WebP vs JPEG?
- WebP is typically 25-35% smaller at the same quality and supports transparency - the best default for modern sites.
- Compress to a specific size like 100KB?
- Enable target-size mode and enter your KB limit; the tool tunes quality to fit. Set a max width for very small targets.
- Are my images uploaded?
- No - everything runs in your browser via Canvas. Files never leave your device.
- Why does image size matter for SEO?
- Heavy images slow LCP, a Core Web Vital and ranking factor, and raise bounce rate. Compression is a top performance win.
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