Compress and convert images in bulk, without uploading them
Drop a batch of photos or screenshots and Shrinkmoor compresses them on your own device with MozJPEG, libwebp, libavif and OxiPNG compiled to WebAssembly. Convert between JPEG, PNG, WebP and AVIF, resize, strip metadata (with rotation applied), and download everything as one ZIP. PNG screenshots are reduced to at most 256 colours first, so they shrink the way they do on palette-based compressors. If a result would come out bigger, you keep the original.
Measured on the live app's two samples at quality 75
| Sample | Original | MozJPEG | WebP | AVIF |
|---|---|---|---|---|
| photo.jpg (1024x1024 photo, JPEG q95) | 225 KB | 57 KB (-75%) | 34 KB (-85%) | 24 KB (-89%) |
| screenshot.png (1440x1000 store screenshot) | 278 KB | 98 KB (-65%) | 74 KB (-74%) | 66 KB (-76%) |
Source: Shrinkmoor measured results, 1 Oct 2026, Chromium (products/shrinkmoor/README.md "Measured"; e2e tests/e2e.mjs). The sample photo is AI-made.
Shrinkmoor vs the alternatives
Published prices, each checked on the date shown; prices change, so confirm on each site.
| Product | Price | Free | Checked |
|---|---|---|---|
| Shrinkmoor Pro | $2.99/month or $29/year | 30 images a day, up to 10 MB each | live |
| iLoveIMG Premium | $9/month billed monthly; $60/year billed yearly | 30 image compressions (free plan) | 2026-10-10 |
| Kraken.io | Micro $5/month or $50/year (500 MB); Basic $9/month; Advanced $19/month | 100 MB testing quota | 2026-10-10 |
Why teams pick Shrinkmoor
- Images never leave your device: there is no upload and no server copy.
- Pro at $2.99/month or $29/year, under iLoveIMG Premium ($9/month, $60/year) and Kraken.io Micro ($5/month, $50/year).
- Target file size on Pro: tell it 60 KB and it searches quality, then resolution, until it fits.
- Every modern format in and out, including AVIF, with resize and a single ZIP download.
How it works
- Open Shrinkmoor and drop your images (nothing is uploaded).
- Pick the output format, quality and an optional maximum width or height.
- Download each image or everything as a ZIP.
FAQ
Is there a free bulk image compressor that does not upload?
Yes: Shrinkmoor compresses 30 images a day free, up to 10 MB each, entirely in your browser.
Why not iLoveIMG?
iLoveIMG has more image tools and a bigger free file size, but it processes files on its servers and Premium is $9/month. Shrinkmoor keeps images on your device for $2.99/month.
Why not Kraken.io?
Kraken.io adds an API and plugins with a monthly MB quota from $5/month. If you compress in the browser, Shrinkmoor has no quota on Pro.
Is it as small as other compressors?
On our samples, JPEG to WebP saved 85% and to AVIF 89%; results depend on the image and quality you choose.
Limits?
Pro files up to 100 MB (50 megapixels, for browser memory). HEIC opens only in Safari. GIFs keep only the first frame. No API or WordPress plugin.