Compress and convert images, privately
Large image files slow down websites, fill up storage and are slow to send. ImageBloom makes them smaller and lets you switch between formats in a couple of clicks — and because everything happens inside your browser using the HTML canvas, your pictures are never uploaded to any server. That makes it fast, free and private, even for sensitive photos.
JPG, PNG or WebP — which should you use?
JPG is best for photographs: it compresses smoothly and produces small files, but it has no transparency. PNG is lossless and supports transparency, which makes it ideal for logos, icons and screenshots, though files are larger. WebP is the modern all-rounder — it usually beats both, giving smaller files at similar quality with transparency support, and is supported by every current browser.
How compression works
For JPG and WebP, the Quality slider controls how much detail is kept: lower quality means a smaller file. Around 75–85% is a sweet spot where the savings are large but the image still looks great. PNG is lossless, so the quality slider does not apply to it — to shrink a PNG, converting it to WebP usually helps most.
Resizing
Set a maximum width or height to scale large photos down — often the biggest space saving of all. A 4000-pixel phone photo is far larger than it needs to be for a website or social post. Aspect ratio is always kept, and images smaller than your limit are left untouched.
Compress an image to a target file size
Need a photo under a specific size — say 100 KB for a form or 2 MB for an upload limit? Turn on target size and ImageBloom adjusts the quality automatically until the file fits, so you do not have to guess the right quality setting. It works best with JPG and WebP, where quality can be tuned smoothly.
AVIF and WebP — the modern formats
WebP is supported by every current browser and typically saves 25–35% over JPG at the same quality. AVIF is newer and compresses even harder — often half the size of JPG — which is great for the web, though very old browsers may not open the file. For photos you want to keep or edit later, a high-quality JPG or PNG is the safest choice.
Best settings for web pages vs printing
For websites, resize to the largest size the image is actually shown at (often 1600–2000 px wide is plenty) and use WebP or JPG at 75–85% — this keeps pages fast and helps Core Web Vitals. For printing, keep the original resolution and use a high quality setting or PNG, since print needs far more detail than a screen.