# Free U01 Viewer

Canonical page: https://embroideryfileconverter.com/u01-viewer

Open a U01 embroidery file online to inspect its stitch preview, dimensions, thread sequence, colour changes, jumps and trims. No account required.

## What is a U01 file?

U01 is a machine embroidery format containing stitch commands and production data. Depending on the format and the software that created it, the file may also preserve design dimensions, colour changes, thread information, jumps, trims and machine-specific commands.

## What this viewer checks

The viewer verifies that the filename uses the `.u01` extension, checks the supported file structure, sends the file to the restricted embroidery engine, parses its actual commands and creates both raster and vector stitch previews. It reports:

- design width and height;
- stitch count;
- thread count and available thread colours;
- colour-change count;
- jump count;
- trim count;
- end-command count.

## How to view a U01 file

1. Open the [Free U01 Viewer](https://embroideryfileconverter.com/u01-viewer).
2. Select or drop one `.u01` file up to 50 MB.
3. Choose **Inspect U01 file**.
4. Review the stitch preview, dimensions, thread sequence and production metrics.
5. Open the larger viewer to zoom, pan or download the SVG or PNG preview.

No account is required and viewing a file does not consume a free processing job or purchased credit.

## Format limitation

U01 stores machine commands with limited thread-colour metadata.

## Important limitations

The preview represents the stitch commands stored in the U01 file; it is not a photograph of the final sew-out. Fabric, stabilizer, thread, tension, needle, density and machine settings affect physical production. Always test stitch an unfamiliar design before using final garments or materials.

## Next steps

This format is available as both a readable source and a validated conversion output.

- [Convert the U01 file](https://embroideryfileconverter.com?service=conversion#converter)
- [Browse all 21 embroidery viewers](https://embroideryfileconverter.com/tools)