Image Compressor — compress images to 100KB free
Compress JPG, PNG and WebP images in seconds. Pick a quality level or an exact target size like 100KB, 200KB or 500KB, compare before and after, then download. Everything runs in your browser — your images are never uploaded.
Runs entirely in your browser — nothing is uploaded.
How to compress images without losing visible quality
Image compression removes data your eyes barely notice. Done well, a photo shrinks by 60–90% and still looks identical — which means faster pages, successful uploads and lighter emails.
Quality vs. target size
Quality mode lets you pick a percentage — 80% is the sweet spot for photos. Target-size mode works backwards: choose 100KB, 200KB or 500KB and the compressor finds the highest quality that fits, reducing dimensions only if it has to.
JPG vs PNG vs WebP
JPG is best for photographs and works everywhere. PNG is lossless and keeps transparency, but files stay large. WebP typically beats both by 25–35% at the same visible quality and is supported by every modern browser.
Why smaller images matter
Images are usually the heaviest part of a web page. Keeping them under 100–200KB improves Largest Contentful Paint, a Core Web Vitals metric Google uses for ranking, and makes pages feel instant on mobile data.
Compressing for email
Big images in newsletters and signatures trigger clipping in Gmail and slow loading on phones. Compress logos and product shots before adding them to a mail merge — your recipients on slow connections will thank you.
How to compress an image to 100KB, 200KB or 500KB
- Drag your JPG, PNG or WebP image into the drop area above, or click to browse.
- Choose a target size preset — 50KB, 100KB, 200KB, 500KB or 1MB.
- The tool automatically finds the best quality that fits. If the target is very small for a large photo, it gently reduces dimensions too.
- Compare the before and after previews, then click Download.
This is the workflow upload forms expect: government portals, job applications, exam registrations and marketplaces often reject anything over a fixed limit. Instead of guessing quality percentages, set the exact limit and let the compressor solve for it.
Best practices for web and email images
- Resize before you compress. A 4000px photo displayed at 800px wastes bytes no compressor can recover.
- Use WebP for your own website, JPEG for images you send to others, and PNG only when you need transparency or sharp text screenshots.
- Keep hero images under 200KB and thumbnails under 50KB for a fast, mobile-friendly site.
- Compress signature logos and newsletter images before adding them to campaigns — Gmail clips messages over 102KB of HTML and heavy images slow every open.
- Always check the after preview at full size before publishing, especially text-heavy graphics where artifacts show first.
Working with email campaigns?
Compressed images pair well with the rest of the Mailvern toolbox. Check your message with the Email Spam Checker, preview the layout in the HTML Email Previewer, shrink the code with the HTML Email Minifier, and add a lightweight logo from the Email Signature Generator. Browse everything on the free tools page.
Frequently asked questions
Everything people usually ask about this tool.
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