Batch Image Compressor → ZIP
Compress many images at once with one shared setting and download them together as a .zip.
What is Batch Image Compressor?
The batch version of the Image Compressor: one quality, format and width setting applied to an entire folder, with a per-file before/after report.
How it works
Each image is decoded by the browser, drawn onto a canvas at the chosen maximum width so the aspect ratio is preserved, and re-encoded as JPEG, WebP or PNG. Originals are kept whenever re-encoding would make a file larger, and the results are packed into a single .zip.
- Add your files. Drop files (or a whole folder) onto the drop zone. Browsers hand the contents straight to the page, so nothing is uploaded.
- Choose the options. Pick the format, compression, naming rule or split size. Any change re-computes the preview immediately.
- Download the result. Run the tool and grab the archive, the extracted files or the report. Multi-file results come back as a single .zip.
Examples
A 180 MB product-photo folder → 34 MB
Re-encoded to WebP at 75% quality with a 1600 px width cap — the usual outcome for camera JPEGs that were never resized for the web.
Small PNG icons that refuse to shrink
Lossless PNGs often grow when re-encoded; with “keep the original when compression makes it bigger” on, those files are shipped unchanged.
Common mistakes
Expecting ZIP to shrink photos, video or audio
Those formats are already compressed; deflate typically saves single digits on them. ZIP is at its best on text, JSON, CSV, logs and source code.
Treating ZipCrypto as real encryption
Traditional ZIP encryption is legacy and breakable. It stops casual snooping only — for secrets, encrypt the contents with AES-256 first.
Renaming extensions to convert a file
Changing .png to .jpg does not change the bytes inside. Some programs will refuse the file, or display garbage. Use a real converter when the format must change.
Splitting without keeping the suffixes
The parts carry .001, .002 … suffixes on purpose: the joiner orders them by number and fails loudly when one is missing, instead of producing a corrupt file.
Frequently asked questions
How do I choose between JPEG and WebP?
WebP is typically 25–35% smaller at the same visual quality and supports transparency, so it is the better default for the web. JPEG is worth keeping when a downstream tool or older client does not accept WebP.
What quality should I use?
70–80% is usually indistinguishable from the original at roughly half the size. Below 60% you start to see blocky artefacts around edges and text; above 90% the savings mostly disappear.
Is the EXIF data preserved?
No. A canvas re-encode keeps only pixels, so EXIF, GPS and camera metadata are dropped along with any colour profile the browser does not map. For archival copies, keep the originals.
Can it handle hundreds of images?
Yes, one at a time with progress shown after each file. Very large batches are bounded by the tab's memory since the compressed results are held until the archive is written.