Understanding KB and MB When Preparing Images for Email Newsletters
Size limits are written in kilobytes and megabytes, and the units trip people up. Newsletter images load inside email clients, often on mobile data, so every kilobyte counts toward a fast open.
Recommended settings for email newsletters
| Setting | Starting point |
|---|---|
| Format | JPEG (WebP where accepted) |
| Width | about 1200 px on the long edge |
| Quality | 70 |
| File size | 150 KB or less |
These are practical defaults. If the platform or form you are using publishes its own limits, follow those instead.
Understanding KB and MB When Preparing Images
One megabyte is roughly 1000 kilobytes, and some systems count 1024. If a limit says 100 KB, aim a little under, such as 95 KB, to be safe.
For email newsletters, a target of 150 KB is a comfortable default. Our results panel shows the exact size of each compressed file so you can confirm it before uploading.
Step by step with TheCompressJPEG
- Open the compress JPEG to 150 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 1200 and the target size to 150 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
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.
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.
Wrapping up
For email newsletters, the reliable recipe is simple: resize to around 1200 pixels, compress at quality 70 or to a 150 KB target, and check the result before you upload. Keep the original so you can always start again.
Related guides
- Aspect Ratios to Use for Email Newsletters
Aspect ratio is the shape of the image, and the wrong one leads to awkward crops.
- Converting HEIC to JPEG for Email Newsletters
iPhones save photos as HEIC by default, and not every site accepts it.
- Upload Errors and File Size Limits for Email Newsletters
An upload error is frustrating when the message is vague.
- Quick Guide: Compress JPEG for Email Newsletters in 30 Seconds
Short on time? Here is the fastest route.
- Aspect Ratios to Use for Word Documents
Aspect ratio is the shape of the image, and the wrong one leads to awkward crops.
- Upload Errors and File Size Limits for Scanned Receipts
An upload error is frustrating when the message is vague.