X (Twitter) image sizes
- In-stream image — 1600 × 900 px
- Header — 1500 × 500 px
- Profile picture — 400 × 400 px
Platforms change their layouts from time to time, so treat these as well-established working sizes rather than permanent rules. Uploading an image at the right dimensions means X (Twitter) re-compresses it less, which is the main reason uploads sometimes look softer than the file you started with.
Framing matters more than the number
Crop-to-fill scales the picture until it covers the frame and trims the overflow evenly from the edges — good for photographs, risky for images where something important sits near the border. Fit-inside keeps everything visible and pads the rest, which suits logos and screenshots.
Keeping quality on upload
- Start from the largest original you have, not from a copy that was already posted somewhere.
- Save as JPG or WebP for photographs and PNG for graphics and text.
- Do not upscale a small image to hit a preset — it only looks soft.