Most email services cap attachments at 10–25MB. That sounds like plenty — until you try to send high-resolution photos or design files. A single JPEG from a modern smartphone is 4–8MB. Three photos can hit the limit before you’ve typed a word. The fastest solution: compress before you attach.
Target File Sizes for Email
| Context | Target file size |
|---|---|
| Single image attachment | Under 5MB |
| Multiple images (3–5 files) | Under 3MB each |
| Background images in email body | Under 200KB |
| Inline images in newsletters | Under 100KB |
Method 1: Online Compression (Fastest)
- Open AllMediaTools Image Compressor.
- Upload your image.
- Set quality to 65–75 (sufficient for email preview sizes).
- Click Compress and download.
A typical 5MB JPEG compresses to 400–800KB at quality 70 — well within any email limit, with no visible quality loss at email display sizes.
Method 2: Resize (Most Effective for Very Large Files)
A 4000×3000px phone photo resized to 1920×1440px at quality 75 typically reduces from 8MB to 400–600KB — a 92% reduction. In AllMediaTools, set Max Width to 1920px and enable Maintain Aspect Ratio.
Method 3: Built-In OS Tools
Windows — Paint
Open in Paint → Home → Resize → Pixels → set Width to 1920. Save.
Mac — Preview
Open in Preview → Tools → Adjust Size → set dimensions. File → Export → JPEG → adjust Quality slider.
Email Attachment Limits by Provider
| Email service | Max attachment size |
|---|---|
| Gmail | 25MB |
| Outlook | 20MB |
| Yahoo Mail | 25MB |
| iCloud Mail | 20MB |
| Most corporate servers | 10–25MB (varies) |
Frequently Asked Questions
Will compressing make the image look bad?
At quality 65–75, images look excellent at email display sizes. The difference from the original is only visible if the recipient downloads and zooms in to 100%.
How do I send many large photos?
Upload to Google Drive, Dropbox, or OneDrive and share the folder link. The recipient downloads at full quality with no size restrictions.
Can I compress images on my phone?
Yes — AllMediaTools Image Compressor works fully in mobile Safari and Chrome.