Reduce file size for HMRC Self Assessment
Compress supporting evidence images so they upload faster and pass HMRC Self Assessment portal limits.
Drop your images here
or click to browse
Supports JPEG, PNG, WebP, GIF, BMP
HMRC Self Assessment uploads: why files get rejected
Self Assessment upload issues are usually caused by file weight, not document validity. A receipt photo can look perfectly clear but still fail because the image is too large, too high-resolution, or saved in a format that the portal handles poorly. HMRC flows can also time out on slow connections when attachments are unnecessarily heavy.
In practice, many people submit phone photos that start at 3MB to 10MB each, then hit rejection messages late in the process. Even when a portal allows up to 5MB, smaller files reduce friction, especially when you upload multiple pieces of evidence in one return. Targeting around 2MB is often a safe way to improve compatibility and reliability.
Compression helps by shrinking file size while keeping text and key details legible for review. This tool is built for privacy-sensitive tax documents: everything runs locally in your browser on your own device. No receipt, invoice, or evidence file is uploaded to our servers, stored remotely, or shared with third parties.
How it works
Drop your images
Drag and drop or click to select the images you want to compress.
Automatic compression
Your images are compressed instantly with optimised settings for this use case.
Download
Save compressed images individually or as a single ZIP file.
Frequently asked questions
What file size should I target for HMRC Self Assessment?
Aiming for 2MB per image is a practical target that usually works well across HMRC-related upload flows while keeping good readability.
Can I compress multiple supporting documents together?
Yes. You can drop multiple images at once and compress them in one batch before uploading to HMRC.
Will receipt text still be readable after compression?
For most receipts and invoices, yes. The compressor balances quality and size so the text remains legible while reducing upload weight.
Are HMRC documents uploaded anywhere else?
No. Compression happens in-browser on your device, and files are not sent to or stored on our servers.