Know your formats
Supported formats and limitations
Accepted formats are checked from file contents. Native browser codec support is required. Only still images are supported.
- Input formats
- JPGPNGWEBP
- Output formats
- JPGPNGWEBP
- Centered crop can remove edge content. Fit mode can add transparent padding in PNG/WebP or the chosen background in JPEG.
- Thumbnail exports discard detail and metadata; keep your full-resolution source.
Fit shows the entire image with padding where its proportions differ from the target. Crop fills the thumbnail and removes outer edges from the center. Presets include 150 × 150, 320 × 180 and 640 × 360 pixels, with custom dimensions available. Check the framing before downloading.
Limits: 16 MiB per file, 8192px per edge, 8 megapixels. Batch input is limited to 8 files / 32 MiB, and retained batch outputs to 64 MiB. Metadata is discarded; color profiles and HDR may change.
A local workflow
How to use this converter
Your file contents stay in the browser as you work.
Choose the source image.
Set thumbnail dimensions and choose fit or crop.
Check the framing and export the thumbnail.
A little more clarity
Frequently asked questions
Will a square thumbnail always show the entire image?
Fit mode can retain the full image with padding. A filled square crop may remove edges.
Is Image Thumbnail Maker available now?
This tool runs locally with JavaScript enabled. Check its supported formats and size limits before converting.