Resize image for X (Twitter) Post (1600×900)
X displays single in-feed images at a 16:9 ratio by default. Uploading at 1600×900 keeps your image at full-bleed in the timeline without any awkward crop boxes.
A single in-feed image on X displays at a 16:9 ratio, and 1600×900 pixels is the practical export size. X crops other ratios to 16:9 for the timeline preview and requires a tap to see the full frame, so matching 16:9 up front is what keeps your composition intact for people who never tap. Images are capped at 5 MB for JPG and PNG and 15 MB for GIF, and the long edge is limited to about 4096 pixels. PNG is worth using for screenshots and charts, where X's JPEG re-encode otherwise softens thin lines and small type badly. If you are posting several images, plan for the multi-image grid instead: two sit side by side at roughly 1:1, and three or four tile into smaller rectangles with tighter crops than the single-image case.
Drop an image to resize to 1600×900
JPG or PNG
Why does X crop my image in the timeline?
X applies a 16:9 preview crop to single images in the timeline. A portrait photo is not shown tall; it is cropped to a wide strip taken from the centre, with the rest hidden behind a tap. Multi-image posts crop more aggressively still — two images sit side by side at roughly 1:1 each, three or four are tiled into smaller rectangles, and the crops in those layouts are tighter than the single-image case. On the encoding side, X re-encodes uploads as JPEG and caps the long edge around 4096 pixels. A 1600×900 export is comfortably inside that ceiling while still being sharp on high-density displays, where the image renders around 600 CSS pixels wide. Going much larger provides no visible benefit and increases the chance of the platform's compression being applied more aggressively.
Multi-image layouts and format handling
The 16:9 rule applies cleanly only to single-image posts. As soon as a post carries two or more images the layout changes and each image is cropped to fit a tile, so a set designed at 16:9 will not display as four neat widescreen frames. If you are posting a set, design each image closer to square so the tile crop takes less. PNG uploads containing photographic content are sometimes converted to JPEG despite the format, which surprises people posting screenshots with fine text — the workaround is to keep screenshot images small enough in byte size that X leaves the PNG intact, or accept the conversion and increase the source contrast. Alt text is worth adding on every image; it is the only part of an image post that is machine-readable and it is frequently omitted.
Getting screenshots and charts to survive the feed
Screenshots and data charts are the most common thing posted to X and the most likely to come out unreadable, because they combine fine type with a platform JPEG pass. Three things help. First, crop tightly — a full-window screenshot scaled to 1600 pixels wide leaves the actual content tiny, so crop to the region that matters before resizing. Second, increase contrast; mid-grey text on a light-grey background is legible on your monitor and mush after compression. Third, if the source is a chart or diagram, consider Fit rather than Fill so nothing is trimmed, and accept the padding. For photographs the calculus is different: Fill at 16:9 is almost always right, because the crop removes background rather than information. Whichever you choose, previewing the post before sending shows the exact timeline crop and takes a few seconds.
X Post tip: match the 16:9 in-feed crop exactly
X auto-crops other ratios to 16:9 in the timeline preview; users have to tap to see the full image. Resize first to guarantee your composition stays intact.
Twitter / X Post size FAQ
Will my image look the same on mobile and desktop?
- For single-image posts, yes — 16:9 is the preview shape on both. Multi-image posts use tiled layouts that crop differently.
What resolution should I upload?
- 1600×900 is the sweet spot. X caps the long edge around 4096 pixels, but larger files bring no visible gain and invite heavier compression.
Why did my PNG screenshot turn into a JPEG?
- X converts larger PNG uploads with photographic content to JPEG. Crop tightly and raise contrast so the conversion does less visible damage.
How do I stop X cropping my portrait photo?
- You cannot change the preview crop, but resizing to 16:9 first means you choose what is lost rather than the platform choosing for you.
Does the same size work for a set of four images?
- No. Four-image posts tile into a 2×2 grid and crop each tile, so design those closer to square.
What is the file-size limit?
- X accepts images up to 5 MB. A 1600×900 JPEG is typically 200–500 KB.
Should I add alt text?
- Yes. It is the only machine-readable part of an image post and it is what screen-reader users receive.
Is my file uploaded to resize it?
- No. The canvas resize happens in your browser and the output never leaves your device.
How X crops by post type
| Post type | Preview shape | Design guidance |
|---|---|---|
| Single image | 16:9 wide crop | Export at 1600 × 900 |
| Two images | ~1:1 each, side by side | Design closer to square |
| Three images | One large, two stacked | Keep subject centred |
| Four images | 2 × 2 tiles | Expect a tight crop on each |
Only single-image posts honour 16:9 — multi-image layouts re-crop each tile.
Last updated:
References: X Help Center media specifications and supported formats; timeline crop and re-encode behaviour verified against the X web and iOS clients.