How to compress an image
- Add your images. Drop them on the box above, click Choose images, or paste a screenshot with Ctrl+V (Cmd+V on a Mac). They are processed one at a time, so the page stays responsive.
- Pick a format. Same keeps JPEGs as JPEG and PNGs as PNG. Choose WebP to convert images for a website, or JPEG when the file must open anywhere.
- Set the quality or a target size. 80 suits most photos. Or switch to Target size, type a limit such as 200 KB, and the tool finds the highest quality that fits.
- Resize if the image is bigger than it will ever be shown. A max width or height usually saves more than any quality setting. Images are never enlarged.
- Check and download. Click Compare to drag a before/after slider, zoom to 100% to inspect detail, then download files one by one or all together as a ZIP.
How image compression works
Lossless compression keeps every pixel exactly and saves space by describing repeated patterns efficiently. It suits logos, screenshots and flat colour, and does little for photos. Lossy compression throws away detail your eye is unlikely to miss, such as tiny colour shifts in fine texture. The quality setting decides how much goes. Dropping from 100 to around 80 usually makes a photo far smaller with no visible change; below about 50, blocky patches and smeared edges start to show.
| Format | Compression | Transparency | Best for |
|---|---|---|---|
| JPEG | Lossy | No | Photos, and files that must open anywhere |
| PNG | Lossless | Yes | Logos, screenshots, graphics with text |
| WebP | Lossy or lossless | Yes | Website images; usually smaller than JPEG at similar quality |
| AVIF | Lossy or lossless | Yes | Very small web photos; slow to encode |
This tool reads AVIF when your browser can, but saves as JPEG, WebP or PNG, because most browsers cannot create AVIF files from a web page. Target size mode works by trial: it saves at quality 95, then 10, then keeps splitting the difference, up to eight attempts, and keeps the best result under your limit.
Worked example: why resizing matters most
A typical 12-megapixel phone photo is 4032 × 3024 pixels, or 12.19 million pixels. Resized to 1600 pixels wide it becomes 1600 × 1200, which is 1.92 million pixels: about 16% of the original. The encoder has roughly a sixth as much to store before the quality slider does anything, and on a page that shows the photo 800 pixels wide, nobody can see the difference.
Recommended image sizes
A simple rule: export at about twice the width the image is displayed at, so it stays sharp on high-density screens, and no bigger.
| Where it is used | Longest side | Format and quality |
|---|---|---|
| Full-width website banner | 1920–2560 px | WebP or JPEG, 70–80 |
| Blog and page images | 1200–1600 px | WebP or JPEG, 75–80 |
| Portfolio pieces | 2000–2500 px | WebP or JPEG, 80–85 |
| Email, inline or attached | 800–1200 px | JPEG, 70–80 |
| Social media posts | The platform's recommended size | JPEG, 85–90 |
| Logos, icons, screenshots | Twice the display size | PNG or WebP |
Email layouts are usually around 600 px wide, so bigger inline images only slow the inbox down. Social platforms recompress whatever you upload, so give them a clean, high-quality file at the size they ask for rather than a pre-crushed one.
Why smaller images make a faster site
Images are usually the heaviest files on a portfolio or small-business site, and each one has to download before the page looks finished, which hurts most on mobile data. Google's Core Web Vitals include Largest Contentful Paint, and on many pages the largest element is a hero image, so one oversized banner can make the whole page feel slow. Lighter images also use less hosting bandwidth. If you build sites for clients, compressing images before launch is one of the quickest speed wins you can deliver.
In-browser compression vs upload sites
Many online compressors upload your files to a server, process them there and send them back. That is fine for a holiday snap, less so for unreleased product shots, client work under NDA or a scanned passport. This tool uses your browser's own image engine: files are read from your disk into this tab and never sent anywhere. You can test it yourself: load the page, turn off Wi-Fi, and compress a file.
Re-encoding also strips EXIF metadata, which can include the GPS position where a photo was taken, the camera model and serial number, and the date. That makes it a quick way to clean photos before posting them publicly or sending them to a client.
Common mistakes
- Re-compressing the same JPEG. Each lossy save loses a little more detail. Keep your originals and always compress from them.
- Saving photos as PNG. A photo stored losslessly is often several times larger than a good JPEG or WebP.
- Saving logos and screenshots as JPEG. Text and sharp edges pick up fuzzy halos. Use PNG or WebP.
- Letting the website shrink a full-size photo. Visitors still download every pixel, even when the image is shown small.
- Setting quality to 100. The file often ends up bigger than the original with no visible gain.
Frequently asked questions
Are my images uploaded to a server?
No. Your browser decodes, resizes and re-encodes the images on your own device, and nothing is sent to Freelance Toolbelt or anyone else. Images are never stored either; only your settings are remembered, in this browser.
Why is the compressed file bigger than the original?
The original was already well compressed, or the new settings ask for more data: a higher quality, or a less efficient format such as a photo saved as PNG. When the result is bigger and the format and dimensions are unchanged, the tool keeps your original automatically, and you can switch to the compressed version with one click.
What quality setting should I use?
Start at 80 for photos. Try 70 to 75 for website images where speed matters most, and 85 to 90 for portfolio pieces or anything a social platform will compress again. Check skies, skin and text with the Compare slider at 100% zoom before you decide.
Should I convert to WebP or keep JPEG?
For your own website, WebP is usually the better choice: smaller files at the same visual quality, support for transparency, and every current major browser can show it. For email attachments, documents and files a client will open in older software, JPEG is the safer choice.
How do I get an image under a specific size, like 100 KB?
Set Compress by to Target size and enter the limit. The tool tests up to eight quality levels and keeps the highest one that fits. If it still cannot get there, set a smaller max width or height, because fewer pixels is the most effective way to cut file size.
Can I compress HEIC photos from an iPhone?
Only if your browser can open HEIC files, and most browsers other than Safari cannot. If you get an error, export the photo as JPEG first, or set the iPhone camera format to Most Compatible so new photos are saved as JPEG.
Does compressing remove EXIF data and GPS location?
Yes. Re-encoding writes a fresh file without the EXIF block, so the GPS location, camera details and capture time are removed. Photos are turned the right way up first, so they do not end up sideways. A file you choose to keep as the original keeps its metadata.
Does it work with animated GIFs?
Only the first frame is kept, and it is saved as a still image. The tool tells you when a GIF is animated, so you are not caught out.