--- title: "X Bio and Alt Text Checker: Limits, Handle Rules and Tips" description: "Check your X display name, handle, bio and image alt text against their limits and rules, with a live profile preview. Private, in your browser." url: https://kairopost.com/tools/x-bio-checker --- # X bio and alt text checker On X a display name can be 50 characters, a username 15, a bio 160 and an image description 1,000. Check every field against those limits and X's username rules, with a live profile preview. - Runs in your browser - Nothing uploaded - No sign up Live. Everything runs on your device. Nothing is uploaded ## How to check your X bio It takes a minute, and nothing you type leaves your browser. 1. ### Fill in your profile: Type your name, username, bio, location and website over the example. 2. ### Watch the meters: Each limited field turns amber near its limit and red when over. 3. ### Read the checks: Red lines are X rules that would stop a save; amber lines are advice. 4. ### Write an image description: Paste alt text for a post image and check it against 1,000 characters. 5. ### Check the preview and copy: Read the live card as a visitor would, then copy each field into X. ## X profile character limits Each limit links to the X Help Center. Where X publishes no limit, we say so. - 50: ### Display name: [Source](https://help.x.com/en/managing-your-account/change-x-handle) - 15: ### Username: [Source](https://help.x.com/en/managing-your-account/change-x-handle) - 160: ### Bio: [Source](https://help.x.com/en/managing-your-account/how-to-customize-your-profile) - 1,000: ### Image description: [Source](https://help.x.com/en/using-x/write-image-descriptions) - None: ### Location: [Not published](https://help.x.com/en/managing-your-account/how-to-customize-your-profile) - None: ### Website: [Not published](https://help.x.com/en/managing-your-account/how-to-customize-your-profile) Won't save: a fake check mark in the name or bio. Angle brackets and quotes in a bio are not shown. ([X Help](https://help.x.com/en/managing-your-account/cant-save-changes-to-my-account)). For posts, use the [X character counter](https://kairopost.com/tools/x-character-counter). ## X username rules - ### Length: More than 4 and up to 15 characters. - ### Characters: A to Z, 0 to 9 and underscores. No spaces, dashes or dots. - ### Reserved words: Admin and X's brand name are for official accounts. - ### Availability: X does not release inactive names, and this checker cannot see which are taken. Sources: [changing your username](https://help.x.com/en/managing-your-account/change-x-handle) and [username registration](https://help.x.com/en/managing-your-account/x-username-rules). Taken? X suggests adding an underscore. Sample usernames, checked live - @jonas_ben: Passes every documented rule. - @relay.dev: Only letters A to Z, numbers and underscores are allowed. Found: . - @maya lindqvist: Only letters A to Z, numbers and underscores are allowed. Found: space - @ab: X's help center says usernames must be more than 4 characters long. - @superlongusername2026: 21 characters. X allows up to 15. - @siteadmin: Contains a reserved word (Admin). Only official X accounts can use it. - @Design_2026: Passes every documented rule. ## How to write alt text for X Alt text is what screen reader users hear instead of seeing your image. Add it with the ALT button. The habits below come from [X's own guide](https://help.x.com/en/using-x/write-image-descriptions). - Capture what matters - Be succinct - Write out text in the image - Spell out abbreviations - Say the image type - Use sentence case - Do not repeat the post ## X bio ideas that fit in 160 characters 12 formulas. Copy one, swap the brackets for your own true details, and check it above. Examples are invented. ## Alt text on every image, without the chore Kairo Post drafts a description for every image it publishes, which you can edit, and sends both to X together. See the [images and media feature](https://kairopost.com/features/visuals), or browse more [tools for X](https://kairopost.com/tools). ## X bio and alt text questions ### How long can an X bio be? Up to 160 characters. X's help center lists a maximum of 160, and a longer bio will not save. ### What is the character limit for an X display name? Your display name, shown above your username, can be up to 50 characters according to X's help center. ### What are the rules for an X username? More than 4 and up to 15 characters, using only letters, numbers and underscores. Usernames containing Admin or X's own brand name are reserved for official X accounts. ### How long can alt text be on X? Image descriptions can be up to 1,000 characters. X's own guidance still recommends being succinct, clear and detailed. ### Why won't X save my bio? X's help center lists a bio over 160 characters, a fake verification check mark in the name or bio, or a link detected as unsafe. Angle brackets and quotation marks in a bio are not displayed. ### Is there a character limit for location and website? X does not publish one, so the checker shows their length without a limit. If X rejects a long entry, shorten it. ### Do emoji count as two characters in a bio? X documents weighted counting for posts, not for profile fields. This checker counts one per character, so leave a little room if your bio uses emoji. ### Is anything I type sent to X or saved? No. Everything runs in your browser, with no sign up and no cost. Nothing is sent to X, uploaded or stored. Written by Jonas Ben , founder of Kairo Post. Updated 30 September 2026 . ## More tools [All tools](https://kairopost.com/tools) - [X character counter Count characters exactly the way X does.](https://kairopost.com/tools/x-character-counter) - [Thread splitter Turn long text into a clean, numbered thread.](https://kairopost.com/tools/x-thread-splitter) - [AI phrase checker Spot the phrases that make writing sound machine made.](https://kairopost.com/tools/ai-phrase-checker) ## Post at the right moment. Starting today. Connect an account, describe your voice and let Kairo Post do the legwork. [Get started](https://app.kairopost.com/signup) [See pricing](https://kairopost.com/pricing)