Image Resolution and DPI Explained: What Size Do You Actually Need?

Resolution. DPI. PPI. Megapixels. These terms get thrown around constantly, but what do they actually mean? And more importantly \u2014 what resolution do you actually need for what you are doing right now?

This guide cuts through the jargon and gives you practical, numbers-you-can-use answers for every common scenario.

PPI vs DPI: What is the Difference?

PPI (Pixels Per Inch) describes how many pixels are in one inch of a digital image displayed on a screen. A 300 PPI image has 300 pixels packed into every linear inch. DPI (Dots Per Inch) describes how many ink dots a printer places in one inch of paper. These are different things, though people use them interchangeably.

What Resolution Do You Need for Different Uses?

Social media (2026 specs): Instagram posts work best at 1080x1080px (square) or 1080x1350px (portrait). Facebook shared images: 1200x630px. Twitter/X in-stream images: 1600x900px. LinkedIn posts: 1200x627px. Pinterest: 1000x1500px (2:3 ratio). Use the Resize tool (https://www.iamuu.com/image/resize/) to hit these exact dimensions.

Email attachments: Keep images under 1MB total for reliable delivery. Most email clients display images at 600-800px wide, so resize accordingly. There is no benefit to attaching a 6000x4000 photo to an email \u2014 it will be displayed at a fraction of that size.

How to Resize Without Losing Quality

Use the Resize tool (https://www.iamuu.com/image/resize/) and enter exact pixel dimensions. Keep the aspect ratio locked to avoid stretching. Verify at 100% zoom before saving.

Quick Reference: Resolution by Use Case