Image Compressor Online – Compress JPG, PNG & WEBP Free

100% Private Runs in Your Browser PNG Quantization Free & Unlimited

Image Compressor

Reduce image file size while keeping excellent visual quality — directly in your browser. JPG and WEBP via smart quality control, PNG via true color quantization (the technique professional optimizers use), plus target-file-size mode. No uploads, no servers, no sign-up.

1. Upload Images

Drag & drop your images here

or

Browse Files

JPG, PNG, WEBP, BMP, GIF (first frame) & AVIF where your browser supports them · Maximum 50 MB per file · Up to 50 images per batch

…or choose files from your device

Selected images 0

Status badges under each thumbnail update during compression.

2. Compression Settings

Compression mode

Compression quality 80%

For JPG, WEBP and AVIF. Higher keeps more detail but saves less space.

Target file size per image

KB MB

Qualities are searched automatically per image. If your target isn't reachable without severe quality loss, the best attempt is provided and clearly flagged.

Output format Keep Original Format JPG PNG WEBP AVIF

PNG optimization Auto — 256 colors + dithering (recommended) Quantize — 256 colors Quantize — 128 colors (smaller) Quantize — 64 colors (smallest) Off — lossless PNG (no quantization)

Applies whenever the output is PNG (including BMP/GIF sources and transparent images). Smart quantization is what makes PNG files genuinely smaller — the lossless and quantized versions are compared and the smaller one wins automatically.

Max width (optional)

Max height (optional)

Filename suffix

Dimensions are preserved by default — the optional max width/height only ever scales down, never up, and never distorts the aspect ratio. Images above 8192 px are scaled down for browser stability. JPG output cannot store transparency — transparent areas become white; PNG and WEBP keep transparency.

Compressed locally — your images never leave this device.

Compressing…

Preparing images…

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3. Compression Results

How to Compress Images Online

1. Upload one or multiple images using drag & drop or the file browser.
2. Choose a compression mode: Smart (automatic), Low/Medium/High presets, Custom quality, or Target Size when you have a specific file limit.
3. Optionally choose a different output format — WEBP or AVIF often compress better than JPG when your browser supports them.
4. For PNG, the PNG optimization setting controls smart color quantization — Auto (256 colors + dithering) is recommended and dramatically shrinks most PNGs.
5. Click Compress Images and follow the progress bar.
6. Review the before-and-after previews plus exact sizes and percentage saved.
7. Download individual compressed images, or grab the whole batch as a ZIP archive.

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How PNG compression really works: PNG is lossless, so quality sliders do nothing for it. Real PNG optimizers reduce the image to a small color palette with dithering, which makes the data compress far better — that's exactly what this tool's quantization does. The lossless and quantized versions are compared and the smaller file always wins.

100% local processing: compression happens entirely inside your browser using the Canvas API. Images are never uploaded, transmitted or stored — the tool even works offline once loaded, and your original files are never modified.

Frequently Asked Questions

Each image is decoded in your browser, rendered to a canvas, and re-encoded with your chosen format — JPG/WEBP via quality control, and PNG via smart color quantization with dithering. The result is a genuinely new, smaller image file — never a renamed copy.

Yes — completely free and unlimited. No registration, no watermarks and no hidden limits. Compress as many images as you like.

No. All processing runs locally inside your browser. Your files never leave your device — the tool keeps working even if your internet connection drops after the page has loaded.

Inputs: JPG, JPEG, PNG, WEBP, BMP, GIF (first frame) and AVIF wherever your browser can decode them. Outputs: the original format, JPG, PNG, WEBP and AVIF — with WEBP/AVIF clearly labelled and disabled if your browser can't encode them.

Photos exported as JPG or WEBP at 60–80% quality commonly shrink by 50–90%. PNGs shrink substantially through quantization — screenshots and graphics often drop 60–90%, photos 40–70%. The tool always compares variants and keeps the smaller one, and every result shows its exact percentage.

Lossy formats (JPG, WEBP, AVIF) trade a little quality for a lot of size — at 80%+ quality the difference is usually invisible. PNG quantization limits the palette to your chosen number of colors; dithering keeps gradients smooth, so most images look unchanged. If quantization ever produces a larger file, the lossless version is kept automatically instead.

Yes — up to 50 images per batch. Every image is processed sequentially with the same settings to keep memory usage low, with live per-file status, then you can download each result or the whole batch as a ZIP.

Yes — use Target Size mode. The tool binary-searches compression qualities to land just under your limit (in KB or MB). If the target isn't reachable without severe quality loss, the best attempt is delivered and clearly flagged with the achieved versus requested size.

For photos: WEBP usually beats JPG at equal quality, and AVIF can beat both — if your browser supports encoding them (the tool detects this automatically). For graphics and screenshots, quantized PNG often wins while staying perfectly crisp. Smart mode picks a sensible format for you.

Absolutely. The tool is fully responsive and touch-friendly, and works in modern mobile browsers such as Chrome and Firefox on Android, and Safari on iOS.

Yes — and this tool handles each correctly. JPG is lossy: the quality slider directly controls the size/detail trade-off. PNG is lossless: instead of a useless quality slider, this tool uses color quantization — reducing the image to a smartly chosen palette (256/128/64 colors) with Floyd–Steinberg dithering so gradients stay smooth. That's the same core technique behind famous PNG optimizers, and transparency is preserved throughout.

Very detailed or very large images carry a lot of information — pushing quality down still may not hit an aggressive target. The tool stops at a minimum acceptable quality rather than destroying the image, gives you the smallest honest result, and shows exactly what was achieved versus what was requested. Optional max-dimension resizing usually closes the gap.

Privacy notice: all image processing happens locally inside your web browser. Your images are never uploaded to a server, transmitted over the internet, or shared with third parties. Uploaded images remain on your device during processing, and originals are never modified or overwritten.