Lossy vs Lossless Compression for Signature Uploads
Image compression comes in two flavours. Signature images are simple black-on-white marks, so they can be very small while staying perfectly legible.
Recommended settings for signature uploads
| Setting | Starting point |
|---|---|
| Format | JPEG (WebP where accepted) |
| Width | about 300 px on the long edge |
| Quality | 60 |
| File size | 20 KB or less |
These are practical defaults. If the platform or form you are using publishes its own limits, follow those instead.
Lossy vs Lossless Compression
Lossless compression, as in PNG, keeps every pixel exactly and saves modest space. Lossy compression, as in JPEG and WebP, discards detail the eye barely notices and saves far more.
For photographs used for signature uploads, lossy is the practical choice. Save lossless formats for graphics where every pixel edge matters.
Step by step with TheCompressJPEG
- Open the compress JPEG to 20 KB tool, or the main compressor for custom settings.
- Drop in your image. Nothing is uploaded; it is processed in your browser.
- Set the maximum width to 300 and the target size to 20 KB.
- Press Compress, check the result and download it.
Quick tips
- Check the result on a phone, where most people will see it.
- Use consistent dimensions for a set of related images.
- Resize before you compress; it improves quality at any file size.
- Write a size limit slightly below the stated maximum to leave a margin.
FAQ
How do I compress many images for e-learning courses at once?
Drop all of them into the tool together and use Download all to get a single ZIP.
What JPEG quality should I use for e-learning courses?
Quality around 78 keeps photos looking natural while cutting file size substantially.
Will compressing reduce image quality for e-learning courses?
Some detail is removed, but at sensible settings the difference is not visible at normal viewing size.
Wrapping up
For signature uploads, the reliable recipe is simple: resize to around 300 pixels, compress at quality 60 or to a 20 KB target, and check the result before you upload. Keep the original so you can always start again.
Related guides
- Compressing Photos With Text for Signature Uploads
Text inside photos, like signs or slides, needs a gentler touch.
- Compressing Portrait Photos for Signature Uploads
Faces are where viewers notice compression first.
- Compressing Product Photos for Signature Uploads
Product photos must look accurate because people judge the item by them.
- Naming and Organizing Compressed Images for Signature Uploads
Good file names help you, your team and search engines.
- Compressing Photos With Text for Slack Messages
Text inside photos, like signs or slides, needs a gentler touch.
- Compressing Product Photos for Cloud Backups
Product photos must look accurate because people judge the item by them.