Twitter/X Image Resizer

16:9 at 1600x900 displays nearly full in most timeline contexts, and 1080x1350 portrait gets generous vertical space on mobile. Extreme ratios, very tall or very wide, are the ones the feed truncates hardest.

The 1500x500 header gets cropped differently per screen width, and your profile photo overlaps the lower left corner. Keep important header content vertically centered and away from that corner.

It gives you consistent source files; the collage itself is X's doing. Two images split into side by side columns, and four become a compact grid of wide tiles. Uploading matching ratios keeps a collage looking deliberate.

Yes, the Card summary preset outputs 1200x630, the shape used by summary_large_image link previews. That's the image people see when your URL gets shared, so it deserves the same care as a native post image.

PNG screenshots of modest size usually pass through intact; large JPG photos get recompressed. Exporting at the display resolution, like 1600x900, keeps the platform's compressor from mangling fine text in charts and screenshots.

Yes, X renders the avatar at 400x400 at its largest and much smaller in feeds and replies. The tool crops it square; the circular mask is applied by X, so keep the subject centered away from corners.

Post it at 1600x900 with Contain mode if the chart's edges carry axis labels. Cropping the axes off a chart with Cover mode is the most common way data posts go wrong on the platform.

The Header preset outputs 1500x500, the twitter banner size the tool uses for the profile banner strip. It crops differently across screen widths and your avatar overlaps the lower left, so keep key content centered.

No. The twitter banner dimensions come from the Header card at 1500x500, a wide 3:1 strip, while a post is 1600x900. They're kept as separate cards because reusing one shape for the other crops badly.

The Post card exports 1600x900, so that 16:9 shape is the twitter post size and twitter post dimensions the tool defaults to. It shows nearly in full in most timeline contexts, unlike very tall or very wide crops.

For one image the tool's 1600x900 Post preset is the reliable twitter photo size; a portrait alternative sits at 1080x1350. Either way the twitter image size you upload sets how much the feed shows before someone taps in.

Upload at the display resolution the tool provides, 1600x900 for a standard post; that twitter post image size keeps text and charts legible after X recompresses the file. Going much larger just gives the compressor more to throw away.

There isn't a single twitter size that covers posts, headers, cards, and avatars, which is why the tool ships five presets. Pick the card that matches where the image goes rather than forcing one shape everywhere.

It's the other way around. Rather than a twitter image size checker that flags whether your file matches, it outputs each preset at the correct pixels, so the result always fits. Upload once, download the shapes you need.