How to use this tool
- 1Add your JPG or JPEG photos.
- 2Choose a preset, or set the quality slider (70–85 suits most photos).
- 3Optionally resize photos that are larger than needed.
- 4Compress, compare, then download.
Supported formats
- Input
- JPG, JPEG, JFIF (PNG and WebP are also accepted and converted)
- Output
- JPEG by default
Features
- MozJPEG progressive encoding with optimised Huffman tables
- Quality slider from 1 to 100, plus presets
- Photos stay upright: EXIF orientation is applied to the pixels
- Your original is kept if re-encoding would not make it smaller
Better JPEG compression with MozJPEG
SlimMyFile uses MozJPEG, an encoder developed by Mozilla that produces smaller JPEG files than standard encoders at the same visual quality, using progressive encoding and optimised Huffman tables.
Which quality should I use?
As a rule of thumb:
- 85–90: near-identical to the original, for photos you may print.
- 70–80: the sweet spot for websites, email and social media.
- 50–65: very small files where some softness is acceptable.
Reduce dimensions for the biggest savings
A 12-megapixel phone photo is about 4000 pixels wide. If it will be shown at 1200 pixels, resizing first removes about 90% of the pixels, which usually shrinks the file far more than lowering the quality. Use the resize option to set a percentage or exact pixel size.
Your privacy
Files are read and processed by your browser on this device. They are not uploaded, stored or shared, and closing the page discards them. Processing speed and the largest file you can handle depend on your device.
Frequently asked questions
Is JPG the same as JPEG?
Yes. JPG and JPEG are two file extensions for the same format. SlimMyFile accepts .jpg, .jpeg and .jfif files.
Does compressing a JPEG again reduce quality each time?
Each lossy re-encode can lose a little detail. Compress from your original photo where possible, and avoid repeatedly compressing the same file.