Guide · 5 min read
How to Reduce Image File Size
Make photos and screenshots smaller for the web, email and forms: quality settings, resizing and format choice explained.
Last updated: 2026-09-29
Tools for this guide
Resize dimensions first
File size scales with pixel count, not just quality. A phone photo at 4032×3024 shown in an 800px-wide article carries about 25 times more pixels than displayed.
Use the Image Resizer to match the actual display size (plus a little margin for high-density screens, typically 2x at most).
Then tune quality
The Image Compressor's quality slider is the main lever for JPG and WebP. Photos usually shrink 50–85% at balanced quality; screenshots with flat colors shrink less because there's less to discard.
Always compare the before/after preview at full zoom before downloading — banding in skies and blurry small text are the first warning signs you've gone too far.
Pick the right format
Photos: JPG or WebP. Graphics with transparency: PNG or WebP. WebP is typically 25–35% smaller than equivalent JPG — see our JPG vs PNG vs WebP guide for the full decision tree.
PNG output from a compressor helps less than you'd expect, because PNG is lossless; converting photographic PNGs to WebP is usually the bigger win.
Frequently asked questions
What quality setting should I use?
Around 80% is visually indistinguishable from the original for most photos. Drop to 60–70% for thumbnails and previews where nobody will zoom.
Should I resize or just compress?
Do both when the dimensions are larger than needed: a 4000px photo displayed at 800px wastes roughly 25x the pixels. Resize first, then compress.