Batch image optimizer: help & limits

Prepare a set of photos for the web without resizing each one by hand. Set a maximum longest edge and one output format; Reqly keeps each image’s proportions and leaves smaller images at their original dimensions. Review the measured sizes and previews before downloading. The default is WebP, quality 85, with a 1,600-pixel longest edge.

How to use

1. Choose up to ten supported still images.
2. Set the longest edge and output format. Adjust quality if needed, then choose Optimize images.
3. Compare each output’s dimensions and size. Download successful images individually or prepare a ZIP.

Supported files

Still JPG, PNG, WebP, AVIF, BMP, still GIF and supported HEIC. Up to 20 files, 128 MiB combined; 64 MiB each or 32 MiB per HEIC (maximum 10). 64 megapixels per input. Up to twenty images per batch. Maximum 16,384 pixels per edge and 128 MiB output.

How it works

Each image is scaled by the smaller of 1 and your maximum edge divided by its original longest edge. Dimensions are rounded to whole pixels, then re-encoded in a local worker. This never enlarges the image. Quality applies to lossy JPG/WebP; PNG uses lossless encoding of the resized pixels. Files are handled sequentially.

Examples

Limitations

• No guaranteed reduction or exact byte target. Small or already efficient images may become larger. Keep the original when the output does not help.
• Resizing can soften small text. JPG fills transparent areas with white; PNG/WebP retain supported alpha. No HDR or exact metadata/color-profile preservation guarantee.
• No animation. AVIF needs native support; HEIC alpha and multi-image variants are rejected. Limits are 16,384 pixels per edge and 128 MiB combined outputs; low-memory devices may fail earlier.

Privacy

The input set, resizing, encoding and ZIP packaging stay on your device. Names and metadata are not uploaded or logged. Start over releases local references; downloaded files remain on your device.

Common questions