How to Compress Images Without Losing Quality
A 6 MB photo straight from a phone camera is far bigger than any website, email or upload form needs. With two simple steps — resizing and compressing — you can usually cut that to a few hundred kilobytes with no difference you can see.
Why image size matters
Large images slow pages down, push you over email attachment limits, and get rejected by forums and marketplaces that cap uploads. Search engines also factor page speed into rankings, so oversized images quietly cost you visitors.
Step 1: resize before you compress
Most of the wasted size is resolution you will never use. A phone photo might be 4000 pixels wide, but a full-width website image rarely needs more than 1600 pixels, and an in-article image needs about 1000 pixels. Resizing to a sensible maximum width is the single biggest saving — often 70–90% on its own — and because you are removing pixels the eye cannot resolve at display size, there is no visible loss.
Step 2: choose the right format
- JPEG — best for photographs. Small files, no transparency.
- WebP — a modern format that is typically 25–35% smaller than JPEG at the same quality, supported by every current browser. Prefer it when you can.
- PNG — keep it only for graphics with flat colour, sharp edges or transparency (logos, icons, screenshots of text). Saving a photo as PNG makes it larger, not smaller.
Step 3: find the quality sweet spot
JPEG and WebP let you trade quality for size on a scale of roughly 0–100. For photos, 75 to 85 is the sweet spot: files are much smaller, and compression artefacts are invisible at normal viewing distance. Below about 60 you start to see blocky skies and haloing around edges. There is little point going above 90 — the file grows fast for a difference nobody notices.
Rule of thumb: resize to the width you actually display, export as WebP or JPEG at quality 80, and check the result at 100% zoom.
Keep your originals
Compression is lossy and cumulative — every re-save of a JPEG throws away a little more. Always compress from the original, and keep that original file somewhere safe in case you need a different size later.
Doing it in your browser
You do not need to install anything or upload photos to a stranger’s server. Our free Image Resizer & Compressor does the resize and the format choice in one step, entirely on your device — pick a maximum width, set the quality, and it exports whichever of WebP or JPEG comes out smaller. You can drop in a whole batch of photos at once and it will tell you the total space saved.