Bulk Resize Images Online

Resize a whole folder of images at once

Resizing images one at a time is tedious when you have a product catalogue, an event gallery, or a year's worth of phone photos to prepare. This bulk resizer applies the same settings to every file you drop in, then hands back a single ZIP — all without leaving your browser.

How batch resizing works

You set one rule: a maximum long edge in pixels. Each image is scaled so its longest side fits that limit while its aspect ratio stays intact, and images already under the limit are kept as-is rather than upscaled. The tool re-encodes each result in your chosen format and quality, processing files sequentially with a progress indicator so a large batch never freezes the page.

Picking one long-edge limit for a mixed batch

The trick to batching is choosing a rule that flatters every image in the set, not just the average one. Because the limit caps the longest side, a landscape and a portrait shot at the same value end up the same length on their long edge but different on the short — which is usually what you want, since it bounds how much screen any single image can claim. Sensible anchors: 1600–2048 px for web galleries and blog bodies that must stay sharp on retina screens, and 1080–1200 px for social and email where small files matter more than fine detail. Since images already under the limit are left untouched rather than enlarged, you can safely set a generous ceiling and trust that small thumbnails in the same folder won't be blown up.

A repeatable batch workflow

For recurring jobs — a weekly product drop, a monthly newsletter — the value of bulk processing is consistency, so build a routine you can repeat blind:

1. Stage one source folder. Copy the originals you want to process into a single working folder first; never drag from the only copy you have, because the originals stay on disk and you want them to.
2. Name before you resize. The outputs keep their input filenames, so if your store or CMS expects sku-1234-front.jpg, rename the sources to that pattern up front and the ZIP comes out import-ready. Zero-pad numbers (img-001, not img-1) so they sort correctly.
3. Pick one long edge and one format, run the whole set, and you get a flat ZIP of identically sized files in the same order you added them — easy to spot-check against the source folder.
4. Unzip into the destination. Because everything shares a sizing rule and naming scheme, the import is a drag-and-drop rather than a file-by-file chore.

When to use bulk resize

Reach for it when uploading dozens of product photos to a store, trimming a camera dump full of 12-megapixel shots down to web-friendly sizes, standardising a team's screenshots, or preparing image sets for a CMS that rejects oversized files. One pass replaces dozens of manual exports.

Private by design — nothing is uploaded

A two-hundred-image catalogue never touches the network: each file is decoded, rescaled, and folded into the ZIP on your own hardware, so the throughput depends on your processor instead of an upload queue — and confidential product shots stay in the building.

Related image tools

• Image Converter — got HEIC in the pile? Decode the batch before you resize.
• Image Resizer — need exact width and height on one file, not a long-edge cap?
• Image Compressor — push a single output even smaller with a quality slider.
• Image Cropper— reframe the odd image that the one-size rule doesn't suit.