Bulk Image Compressor — JPG, PNG, WebP
Shrink up to 30 photos at once by quality and maximum dimensions, see the saving per file, and download them individually or all together — processed in your browser.
In short
Most of an image's file-size saving comes from resizing: capping the longest side at 1920 px cuts a phone photo by 70–80% before any quality change, and JPG/WebP quality 75 halves it again with no visible loss on screen. PNG only shrinks meaningfully when converted to JPG or WebP.
Who this is for: Website owners, sellers and anyone emailing or uploading many photos who needs them smaller fast.
How image compression works here
- Resizing is where most of the saving comes from: a 4000-px phone photo has 4× the pixels of a 1920-px one, so capping the longest side at 1920 typically cuts the file by 70–80% before any quality change.
- Quality controls how aggressively JPG/WebP discards detail. 75 is standard for the web; most people cannot tell 75 from 95 on screen, but the file is half the size.
- Format: PNG is lossless, so quality does not apply — a photo saved as PNG only shrinks when you switch it to JPG or WebP. Keep PNG for logos, screenshots with text and anything transparent.
- Metadata (camera model, GPS location) is removed in the process.
For a single file that must be under an exact limit (50 KB, 200 KB), use the resize-to-KB tool instead; this one is for batches.
Assumptions
- Longest side capped at the chosen pixels, then re-encoded at the chosen quality in the same or a chosen format.
- Up to 30 files; JPG output flattened on white.
- Metadata removed; no server involved.
Worked example
At 1920 px and quality 75 the batch drops from about 85 MB to roughly 8 MB (−90%), each file 250–400 KB — fast enough to load on mobile and still sharp at full width.
Frequently asked questions
Will compressing reduce the quality visibly?
At 70+ on a resized image, not on screens. Zooming to 200% or printing large may show softening; use 85+ for print.
Why did a PNG get bigger?
Re-encoding a simple PNG in the browser can be less efficient than the original optimiser. Keep the original, or convert it to WebP.
How many images can I compress at once?
30 per batch; very large originals (over ~40 MP) may fail on phones with limited memory.
Is there a size limit or watermark?
No limits beyond your device's memory, no watermark, no account.
How do I reduce photo size without losing quality?
Resize to the size you actually need (1920 px for web) and save at quality 75–85 — invisible on screen, 80–90% smaller.
Can I compress multiple images at once?
Yes, up to 30 per batch with a Download all button.
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