What is Image Compression?
Image compression reduces a file’s size by re-encoding it more efficiently — trading a little (often invisible) detail for a much smaller file. A 4 MB phone photo can usually drop to 300–600 KB with no visible difference on screen. Smaller images upload faster, fit under attachment limits, load web pages quicker, and stop your storage from filling up.
What Makes This Compressor Different
Your image never leaves your device. Most online compressors upload your photo to their servers, process it there, and let you download the result — meaning your personal photos, documents, and screenshots travel to someone else’s computer. This tool does the entire job inside your browser using the canvas API. You can load the page, disconnect from the internet, and it still works. For photos of people, IDs, contracts, or anything private, that difference matters.
How to Use This Tool
- Drop an image onto the box (or click to browse).
- Adjust the quality slider — the result re-encodes live with a before/after preview and size comparison.
- Optionally pick a resize limit: scaling a 4000 px photo down to 1920 px saves far more than quality tweaking alone.
- Choose JPEG or WebP output and click Download.
Quality Settings: a Practical Guide
| Quality | Result | Use for |
|---|---|---|
| 90–100% | Visually lossless, modest savings | Print, portfolios, archiving |
| 75–85% | Sweet spot — hard to spot differences | Web pages, email, social media |
| 60–75% | Slight softness on close inspection | Thumbnails, chat, drafts |
| Below 50% | Visible artifacts | Only when size is everything |
Two levers matter more than people expect: dimensions beat quality (a photo displayed at 800 px wide gains nothing from being 4000 px wide — resizing it saves ~90% before quality even enters), and WebP beats JPEG by roughly 25–35% at the same visual quality, with support in every modern browser.
Why PNG Photos Are Huge
PNG is a lossless format — perfect for screenshots, logos, and graphics with sharp edges or transparency, but wasteful for photographs. A photo saved as PNG is often 5–10× larger than the same image as JPEG with no visible benefit. If you have a PNG photo, converting it to JPEG or WebP here is the single biggest size win available. (Keep PNG when you need transparency or pixel-perfect text.)
Frequently Asked Questions
Is my image really not uploaded anywhere?
Really. The file is read and re-encoded locally by your browser’s canvas engine — no network request carries your image. You can verify by loading the page, switching to airplane mode, and compressing offline.
Does compression reduce image quality?
JPEG and WebP are lossy, so yes — but at 75–85% quality the loss is practically invisible on screens. The live preview shows exactly what you’ll get, so you can find the lowest quality that still looks right to you.
Why did my file get bigger instead of smaller?
It happens with images that were already heavily compressed, or with tiny images where format overhead dominates. The savings badge turns red when this occurs — try a lower quality, a smaller resize limit, or keep the original.
What's the maximum file size?
There’s no fixed limit — processing happens in your device’s memory, so very large images (say, 100+ megapixel panoramas) depend on your hardware. Typical photos up to 50 MB process in a second or two.
Does compressing remove EXIF data (location, camera info)?
Yes — re-encoding through the canvas discards EXIF metadata, including GPS coordinates. That’s a privacy bonus if you’re sharing the image, but export a copy from your photo app first if you want to keep the metadata.
Should I use JPEG or WebP?
WebP produces ~25–35% smaller files at the same visual quality and every modern browser displays it. Choose JPEG when the file must open in older software, office documents, or systems that don’t accept WebP.