Free online image compressor
Pick an image, set the compression quality, then download it. Files are processed on your own device, so there is no upload size limit.
About the image compressor
The BapTools image compressor reduces the file size of JPG, PNG and WebP images directly in your browser, which makes uploads to your website, email attachments and social posts much faster. Because everything runs on your device, your upload speed is never the bottleneck.
When should you compress an image?
- Speed up your website: every 100 KB removed improves page load time and your Core Web Vitals.
- Stay under upload limits: many platforms cap uploads at 2 - 5 MB per image.
- Send images by email: most mail services block attachments above 5 - 10 MB.
- Save phone storage: useful when backing up thousands of photos.
Which quality level should I pick?
A value near 1 keeps almost all original quality but saves little file size. Around 0.7 is the sweet spot for the web: visually almost identical while cutting the file by 50 - 70%. Below 0.5 you will see obvious artefacts, so reserve it for thumbnails.
Real-world examples
Example 1 — 4 MB product photo at quality 0.7
A 4096×3072 original at 4.1 MB comes out around 620 KB, roughly an 85% reduction. On a phone screen nobody can tell the difference.
Example 2 — screenshot for a blog post
A long 900 px screenshot usually weighs 1.8 MB. At quality 0.5 it drops to about 240 KB, which is plenty for an article and noticeably faster to load.
Example 3 — avatars and thumbnails
An image already resized to 400×400 can be pushed to quality 0.4 and still look clean, because small sizes hide compression artefacts.
Example 4 — images containing small text
If the image is a price table or a chart with 8 px text, stay above 0.6. Below that the lettering blurs, and zooming costs the reader more than you saved.
When to use it, and when not to
Worth using
- Phone photos heading to your site, usually 3-5 MB larger than they need to be.
- Email attachments that keep getting rejected for being too large.
- Thumbnails and avatars, where exact colour fidelity does not matter.
- Images queued for social posts, so they load fast and you avoid the platform recompressing them badly.
Not worth it
- Print-ready files. JPEG compression leaves ringing around high-contrast edges.
- Transparent PNG or WebP images: this tool outputs JPEG, so transparency becomes a black background.
- Colour-critical work such as fabric swatches or exact brand-colour matching.
- Images already under 100 KB, where further compression saves nothing and only softens them.
How to compress an image
- Select the image you want to compress.
- Drag the quality slider to choose your level, 0.7 by default.
- Press Compress image and wait for the preview.
- Compare it with the original, then press Download compressed image.
Frequently asked questions
Are my images uploaded to a server?
No. Compression runs with JavaScript inside your browser and your file never leaves your device.
Does compressing reduce image quality?
JPEG and WebP are lossy formats, so any compression discards some original data. You can minimise the effect by choosing a higher quality level.
Is there a limit on how many images I can compress?
There is no fixed limit, but compress one at a time on older phones to keep things responsive.