How to compress an image
- Add your images. Drag and drop JPEG, PNG, WebP, AVIF or GIF files onto the dropzone, click to browse, or paste from your clipboard. Mix formats freely — each file is handled on its own.
- Pick an output format. Leave it on Same format to recompress in place, or choose JPEG, PNG, WebP or AVIF to convert. WebP and AVIF give the smallest files for photos.
- Set quality (and resize if needed). Use the quality slider — around 75 suits most photos — or the lossless level for PNG. Optionally resize by percentage or exact pixels for an even bigger saving.
- Download your results. Save images one at a time or grab everything as a ZIP. Each file shows its original size, new size and percentage saved, so you can re-tune and try again.
Why compress and convert images?
Images are the single heaviest part of most web pages, emails and shared folders. A modern phone camera can produce 4–12 MB photos, and screenshots saved as PNG can be surprisingly large too. Oversized images slow down websites, push email attachments past size limits, fill up cloud storage, and burn through mobile data. Compressing them keeps the detail you actually care about while cutting the file size dramatically — often by 60–90% depending on the format you choose.
This page is the hub for every image format. Because it runs entirely on your device, it is also the private way to do it. Conventional online compressors upload your photos to a remote server, process them there, and send them back. Here, each image is read into memory, re-encoded with a WebAssembly codec, and handed straight back to you. Your pictures never travel across a network, which matters for personal photos, ID scans, contracts and anything else you would rather not hand to a stranger’s server.
Lossy versus lossless: the core tradeoff
Every image format falls into one of two camps. Lossycompression — used by JPEG, and the default modes of WebP and AVIF — permanently throws away detail the human eye is least likely to miss, which is how it achieves such large savings. The quality slider controls how aggressive that is: higher values keep more detail and produce bigger files, while lower values save more space but can introduce visible “artifacts” like blockiness or halos around edges. Lossless compression — used by PNG and GIF, and an optional mode of WebP — rewrites the file more efficiently without discarding a single pixel, so the image is byte-for-byte identical when decoded. The catch is that lossless savings are far more modest.
The practical rule: use lossy formats for photographs and realistic imagery, where a quality of 70–80 is usually indistinguishable from the original, and use lossless formats for graphics, logos, screenshots and anything with sharp edges or text, where lossy artifacts are obvious. Remember that lossy compression is cumulative — always work from your highest-quality master rather than re-saving an already-compressed copy.
Choosing the right format
Picking the format matters as much as the quality setting. As a quick guide: JPEG is the universal choice for photos with no transparency; PNG is best for flat graphics, screenshots and anything needing a transparent background; WebP typically produces files 25–35% smaller than JPEG while supporting both transparency and animation; AVIF is the newest and usually the smallest of all for photographs, at the cost of slower encoding; and GIF is an old animation format that is almost always beaten by converting to WebP or video. The authoritative rundown of how each format behaves in browsers lives in MDN’s image file type and format guide.
If you already know the format you are working with, the dedicated tools give you the most relevant controls and explanations: the JPEG compressor for photos, the PNG compressor for lossless graphics, the WebP and AVIF tools for the smallest modern files, and the GIF compressor for animations. To switch a batch of files from one format to another, use the image converter; to change pixel dimensions, reach for the image resizer.
Practical tips for the best results
- Resize before you compress. If an image will only ever be shown 1200px wide, shipping a 6000px original wastes most of the file. Scaling down usually saves more than the quality slider ever could.
- Match the format to the content. Photos belong in JPEG, WebP or AVIF; logos, icons and screenshots stay sharper and smaller as PNG. Converting a PNG photo to WebP can shrink it by an order of magnitude.
- Keep a master copy. Because lossy re-encoding compounds, always compress from your original rather than from a file you exported earlier.
- Compare before committing.Try “Balanced” first, then re-run at “Smallest” and check whether you can spot the difference at the size you will actually display the image.
- Batch similar images together. Photos from the same camera or screenshots from the same screen usually look great at one shared setting, so you can process them in a single pass.