Compress Images for Email Attachments
Most email providers limit attachments to 10–25MB, but images often far exceed what recipients can easily view or download. Compressing to under 1–2MB makes emails load faster and reduces the chance of delivery failure. Our tools compress images entirely in your browser — no file is uploaded anywhere.
Recommended Image Sizes for Email
Gmail has a 25MB attachment limit, Outlook allows 20MB, and most corporate email servers cap attachments between 10-20MB. However, these are maximums — not recommended sizes.
Best practice is to keep each image under 1MB. Here's why:
- Recipients on mobile connections can view images instantly
- Email loads faster in the recipient's inbox
- Lower chance of being flagged as spam by email servers
- Reduces risk of delivery failure
- More professional — shows consideration for recipient's bandwidth
Two Ways to Compress Images for Email
Method 1: Image Compressor (Quality Slider)
Best when you want visual control. Upload your image, adjust the quality slider (75-85% is the sweet spot), see a real-time preview, and download. Perfect when you want to balance quality and file size visually.
Method 2: Compress to KB (Exact Target Size)
Best when you need to hit a specific file size. Enter your target (e.g., 500KB or 1MB), and the tool automatically compresses to that exact size. Perfect when the recipient or email system has strict size requirements.
Frequently Asked Questions
What size should images be for email?
Under 1MB per image is ideal for email attachments. While most email providers allow 10-25MB total, smaller images load faster and are easier for recipients to view and download.
Which tool should I use?
Use Compress to KB if you need an exact target size (like under 500KB). Use Image Compressor if you want to control quality with a slider and see a preview.
Will quality suffer?
At 80%+ quality settings, the difference is imperceptible to human eyes. The visual quality remains excellent while file size reduces by 60-80%.
Is my image uploaded?
No, compression runs entirely in your browser using the Canvas API. Your images never leave your device.