X (Twitter) Image Sizes (2025)
In-stream post image: 1600 x 900 pixels (16:9). This is the optimal size for single-image tweets. Images are displayed at up to 1200px wide in the timeline but having 1600px width ensures crisp display on high-DPI screens.
Header/Banner: 1500 x 500 pixels (3:1). Your profile header is the largest branding surface on X. Note that on mobile, the top and bottom ~60px may be cropped, so keep text centered vertically.
Profile Picture: 400 x 400 pixels. Displayed as a circle at various sizes across the platform. Use a simple, recognizable image.