How many images can I resize at once?

Up to 100 images per batch. All processing happens in your browser using the Canvas API, so there are no server upload limits.

Will my images ever leave my device?

No. Every image is resized locally using your browser's Canvas API. Nothing is uploaded, stored, or transmitted.

Does it upscale small images?

No. If an image is already smaller than the max dimensions you set, it is kept at its original size — it is never upscaled.

What formats are supported for input and output?

Input: JPEG, PNG, WebP. Output: keep the original format, or convert everything to WebP (recommended for web), JPEG, or PNG.

Does the quality slider affect PNG output?

No. PNG is always lossless. The quality slider only applies to JPEG and WebP output. When PNG is selected the slider is hidden.

How is this different from the single Image Resizer?

The single resizer supports presets, fill mode, and background color. Bulk Resize is streamlined for speed: max-dimension scaling across 100 files at once, with format conversion, downloaded as a ZIP.

Bulk Image Resizer

Resize up to 100 images at once. Set max dimensions, pick an output format, download as ZIP — all in your browser, nothing uploaded.

Max Width (px)

Max Height (px) (optional)

Output Format

Quality: 85%

SmallerLarger

Aspect ratio is always preserved. Images smaller than the max dimension are kept at their original size (no upscaling).

Drop images here, or click to browse

JPG, PNG, WEBP · max 25 MB · up to 100 files

How it works

1Drop up to 100 images onto the dropzone (JPEG, PNG, WebP supported).
2Set a maximum width and/or maximum height — aspect ratio is always preserved.
3Choose an output format: keep the original, or convert everything to WebP, JPEG, or PNG.
4Adjust the quality slider for lossy formats (ignored for PNG).
5Click Resize All and watch the progress bar process every file in your browser.
6Download all resized images as a single ZIP — nothing is uploaded to any server.