Free · In your browser · No upload
Compress an image
Shrink file size with a quality slider and see the before and after sizes before you download.
Many images to do? Try compress images in bulk.
Need more than one operation? Open the full editor to combine tools and reorder your edits.
Compression works by discarding detail your eye is bad at noticing, and the quality slider decides how much. We measured the file size at every step from 10 to 100 across seven images, and the resulting curve has a clear shape: steady growth up to about 50, narrowing returns through the 70s and 80s, then a steep climb above 90 that buys almost nothing you can see.
The clearest finding was at the top of the range. Moving from quality 90 to quality 100 inflated our test files substantially — in one case nearly tripling the size — for a difference essentially nobody can perceive. Quality 100 does not mean lossless; it means paying the maximum price for the detail that remains. If you truly need every pixel intact, the answer is PNG.
How it works
- 1
Load the image you want to shrink.
- 2
Choose WebP for the smallest result, or JPEG if the file needs to open anywhere at all.
- 3
Drag the quality slider and watch the projected size. Between 75 and 85 is the sweet spot for photographs — small files with artefacts that are genuinely hard to spot.
- 4
When the projected size looks right, download. If it is still too large, resizing the image is a bigger lever than pushing quality lower.
Frequently asked questions
How much smaller will my image get?
It depends heavily on the picture. In our measurements a landscape photograph dropped to well under a tenth of its lossless size at quality 80, while a densely textured photograph compressed far less because there is less redundancy for the encoder to exploit. The projected size updates live, so you can see the actual answer for your image.
What quality setting should I use?
Use 75–85 for photographs on the web, and 60–70 for thumbnails or anything displayed small, where artefacts vanish at display size. Go above 90 only if something downstream will re-encode the file. Avoid 100 entirely — we measured it costing far more than quality 90 for no useful gain.
Why can I not compress to PNG?
PNG is lossless and has no quality dial to turn — it stores every pixel exactly, which is why it is so large for photographs. To make a photo dramatically smaller, convert it to WebP, which keeps transparency, or to JPEG if there is none to keep.
Does compressing the same image repeatedly make it worse?
Yes, and this catches people out. Quality settings apply each time a lossy file is encoded, so opening a JPEG and re-saving it at 80 does not preserve the original 80 — it adds a second round of loss. Always compress from the best original you have rather than from an already-compressed copy.
Is there a file size limit?
No fixed limit, because the compression runs on your own device rather than on a server with quotas. Very large images simply take longer, and the practical ceiling is your device’s available memory.