Image Compressor
Shrink image file sizes without uploading.
Large photos slow down websites and eat storage — compression at 75–85% quality is visually identical for most uses.
How to use
- Choose a photo.
- Drag the quality slider — 80% is the sweet spot.
- Download the smaller file; the savings are shown.
About this tool
Output is JPG (best size savings); PNG screenshots compress less since they are already optimized.
Your photos are processed locally and never uploaded.
How it works
Lossy formats (JPEG, WebP) expose a quality dial, usually 0–100. Quality 85–90 preserves virtually all perceived detail while cutting size dramatically versus 100; below about 70, blocky artifacts creep into smooth gradients like skies. The size curve is steep at first then flattens — dropping 100 to 85 often halves the file.
PNG is lossless, so compressing it means searching harder for patterns (compression level) or quantizing to fewer colors. A flat illustration saved as 8-bit PNG can be 70% smaller than the 24-bit original with no visible change.
Always compress a copy and compare at 100% zoom before replacing originals — faces and small text are where artifacts show first.
Worked examples
Portfolio photos: Export at JPEG quality 82 instead of 100: a 2.4 MB photo typically drops to around 600 KB — invisible on screen, four times faster for visitors on mobile data.
Before uploading to a CMS: WordPress builds thumbnails from your upload, but the 'full size' original is what lightboxes display. Compress it first so the zoomed view is not a 5 MB download.
Quick reference
| Quality | Use it for | Artifacts |
|---|---|---|
| 90–100 | Print, archival copies | None visible |
| 80–89 | Web photos (the sweet spot) | None at normal viewing |
| 60–79 | Thumbnails, previews | Slight banding in gradients |
| Below 60 | Placeholders only | Obvious blocking |
Frequently asked questions
Will quality suffer?
At 80%+, differences are invisible to most eyes. Drop lower only for thumbnails.
Why JPG output?
JPG compresses photos far better than PNG; transparency is flattened to white.
Are my photos uploaded?
No — 100% on-device.
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