How do I compress an image to under 100KB for email?

Resize to 800px wide first, convert to JPG if it is PNG, then compress at 70% quality. This workflow consistently produces images under 100KB that look good on screens.

What is the best image format for email attachments?

JPG for photographs, PNG only for graphics that need transparency. JPG files are 3-5x smaller than PNG for photo content with no visible quality difference.

Can I compress images for Discord without losing quality?

Some quality loss is inherent in compression. But resizing to 1200px and compressing at 80% quality produces images that look identical to the original on Discord — the platform would recompress them anyway.

How do I make an image small enough for Discord emoji?

Discord emoji must be under 256KB and ideally 128x128 pixels. Use the Resize Image tool to set dimensions to 128x128, then compress if needed.

How to Compress Images for Email & Discord — Under 25MB, Under 1MB

Last updated: March 2026 8 min read Image Tools

The Problem: Files Too Large to Send

Email providers cap attachments at 20-25MB. Discord free users max out at 25MB. Your phone takes 5MB photos. Your design exports are 15MB PNGs. When you need to share images quickly, file size is the barrier. The fix is a 3-step workflow: resize, convert format, then compress. Done right, you can shrink a 10MB image to under 200KB without visible quality loss.

Step 1: Resize to the Right Dimensions

Most images are larger than they need to be. A 4000x3000 photo from your phone doesn't need to be that big for email or Discord — 1200px wide is plenty for viewing on any screen.

Open the Resize Image tool
Upload your image
Set width to 1200px (height adjusts automatically)
Download the resized version

This alone can cut file size by 60-80%. A 5MB photo at 4000px wide becomes ~800KB at 1200px wide.

Step 2: Convert to the Best Format

PNG files are 3-5x larger than JPG for photos. If your image is a photograph (not a graphic with transparency), converting from PNG to JPG saves massive file size.

Open the Image Converter
Upload your resized image
Convert to JPG (for photos) or keep PNG (for graphics with transparency)

Format conversion is lossless in terms of visible quality for photos. A 2MB PNG photo converts to ~400KB JPG with no visible difference.

Step 3: Compress to Hit Your Target Size

Open the Compress Image tool
Upload your image
Set quality level or target file size
Download the compressed result

After resizing and format conversion, compression is the final squeeze. Quality settings of 70-80% are visually identical to 100% for most photos. Going below 50% starts showing visible artifacts.

Quick Reference: Target Sizes

Email attachment: Under 2MB per image, under 10MB total for all attachments
Email signature: Under 100KB — keep it tiny or it slows every email you send
Discord (free): Under 25MB per file. For fast loading, aim for under 2MB.
Discord emoji: Under 256KB, 128x128 pixels. Use Resize Image first.
Slack: Under 1GB technically, but images over 5MB load slowly on mobile
WhatsApp: Automatically compresses, but sending smaller files preserves quality

Why This Workflow Beats Single-Step Compression

Compressing a 10MB image down to 200KB in one step requires aggressive quality reduction — you'll see blurriness and artifacts. But if you resize first (10MB → 1MB), convert format (1MB → 400KB), then compress (400KB → 200KB), each step does gentle work. The result is a 200KB image that looks nearly as good as the original.

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