Image Compressor
Compress JPG, PNG, WebP by quality or target file size
Image Compressor tool
Image Compressor: key facts
- What it does
- Compress JPG, PNG, WebP by quality or target file size
- Category
- Image Tools
- Cost
- Free, with no account, sign-up, or install.
- Your data
- Runs entirely in your browser — the files and text you enter are never uploaded to a server.
- Last reviewed
- . Report an incorrect result.
Understanding the Image Compressor
Photographs and screenshots are almost always the heaviest asset on a page, and a folder of untouched camera exports will happily eat a mail server's attachment limit. This compressor re-encodes JPG, PNG, WebP, GIF, and AVIF files in the browser, giving you two ways to describe what you want: pick a quality level, or name a ceiling in kilobytes and let the encoder work down toward it.
A quality number alone is not the whole story, which is why the output format sits right next to it. Re-encoding a PNG screenshot as WebP routinely strips away most of its weight, because the quality dial genuinely does nothing to PNG output — browsers only apply it to lossy codecs. The tool detects which formats your browser can encode, warns you when a PNG would stay a PNG, and offers the WebP switch in one click rather than letting you drag a slider that cannot help.
Resizing is spelled out rather than hidden. Choose a limit for the longest edge — 3840, 1920, 800 pixels, or none at all — and each result reports its old and new dimensions so you can tell shrinking apart from squeezing. Metadata stripping is on by default, which removes camera and GPS tags from files you are about to publish.
Getting a result
- Add images by dragging them onto the drop zone, browsing for them, or pasting a screenshot straight from the clipboard with Ctrl or ⌘ plus V.
- Start from a preset — Web, Email, Social, or Archive — or set the output format and longest-edge limit by hand.
- Choose between a quality percentage and a target size in kilobytes, then decide whether to strip metadata and whether to fall back to the original when compression would make a file grow.
- Press Compress and watch the per-file progress bars; cancel at any point and the images already finished are kept.
- Drag the before-and-after divider to inspect the result, switch to actual pixels to hunt for artifacts, then grab files one at a time or bundle them into a ZIP.
Reasons to use it here
- Two ways to aim: a fine-grained quality slider for visual control, or a kilobyte target for the times when a form or mail server has drawn a hard line for you.
- Honest about PNG. Rather than implying that a quality dial shrinks lossless files, the interface flags the situation and offers format conversion as the fix that actually works.
- Format conversion is capability-checked. Only encoders your browser really supports appear in the list, so you never receive a file that quietly fell back to something bulkier.
- Files that are already lean are left alone. When re-encoding would add bytes, the original is passed through and labelled, instead of handing you a worse copy of what you started with.
- Failures stay visible. A file that cannot be decoded keeps its place in the list with the reason and a retry button rather than disappearing from the batch.
- Nothing is transmitted. Decoding, encoding, and ZIP packaging all run on your machine, including the background worker script, which is served from this site rather than an outside CDN.
Frequently Asked Questions
Why did lowering the quality barely change my PNG?
Browsers ignore the quality argument when they encode PNG, because PNG is a lossless format — the pixels have to survive intact. A PNG that stays a PNG can therefore only get smaller by being resized. Switch the output format to WebP (or JPEG for photographs) and the quality setting starts doing real work; a screenshot commonly drops by three-quarters or more.
What does target size mode actually guarantee?
It is best-effort rather than a promise. The encoder repeatedly lowers quality, checking the result each round until the file fits under your ceiling or it runs out of attempts, and the size it reached is printed next to each file. A very small ceiling on a very large photograph may be unreachable unless you also cap the longest edge.
Are my dimensions changed without me asking?
Only if you leave a limit selected. The longest-edge control is visible in the settings panel and includes a Don't resize option; whatever you choose, each finished row prints the original dimensions alongside the output dimensions and marks the row when a reduction happened.
Can it handle animated GIFs?
An animated GIF will be accepted, but the result is a still image. Compression works by drawing the picture into a canvas and re-encoding it, and a canvas only ever holds one frame. Files containing animation are detected as they are added and labelled so the outcome is not a surprise.
Does anything about my photos reach a server?
No. Every stage happens inside the page: reading the file, re-encoding it, measuring the result, and zipping the batch. The helper script that runs compression on a background thread is hosted here too, so no third-party request is made while you work.
What happens to EXIF and GPS data?
By default it is discarded, which trims a little weight and removes location and camera details from anything you publish. Unticking the strip option preserves EXIF for JPEG files that come out as JPEG; any conversion between formats drops it either way, so the checkbox explains that limitation inline.
