What is alt text on X (Twitter)?
Alt text (alternative text) is a written description attached to an image that screen readers speak aloud for blind and low-vision users, and that displays when an image fails to load. On X you add it via the 'Add description' option when attaching media, with a limit of 1,000 characters per image.
Good alt text describes what matters about the image in context, not everything in it: 'Line chart showing signups doubling after the June launch' beats 'a chart'. Screenshots of text should have that text transcribed or summarized, since a screenshot is invisible to a screen reader without it.
Beyond accessibility, alt text has a practical side effect: it's machine-readable content attached to your media, which matters as more discovery happens through AI systems that parse posts. Accounts that consistently write alt text also mark themselves as considered publishers to the audience segment that checks.
Frequently asked
Does alt text affect reach?
X has never confirmed a ranking effect. The reliable benefits are accessibility, image-fail fallback, and machine readability; treat any reach claim as folklore.
How do I add alt text to an image on X?
Attach the image, tap 'Add description' (or the ALT badge), write the description, save. On published posts the ALT badge shows the text to anyone who taps it.
Put it to work
Related terms
Write posts, not vocabulary.
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