Free caption tool
Caption grammar checker
Catch the small mistakes that are easy to miss on a phone keyboard before your caption goes live. Paste your caption, choose where you are posting and the checker highlights common spelling slips, mixed-up words, spacing and punctuation, along with platform-specific notes. Fix issues one by one or all at once. It all runs in your browser.
Caption grammar checker
๐ Works in your browser. Nothing you type is sent anywhere.
How to check your caption
- Paste your caption into the box.
- Choose the platform you are posting to.
- Press check. Each issue is highlighted in your text with a short explanation.
- Apply the fixes you agree with, or use fix all, then copy the corrected caption.
What the checker looks for
- Common misspellings such as โalotโ, โdefinatelyโ and โrecieveโ.
- Mixed-up phrases like โcould ofโ, โyour welcomeโ and โthenโ used for comparisons.
- A lowercase โiโ on its own and sentences that start without a capital letter.
- Repeated words, double spaces and missing spaces after commas.
- Runs of punctuation like โ!!!!โ that can look spammy.
- Hashtags broken by an apostrophe, empty hashtags and repeated hashtags.
- Captions that run past a platformโs length, such as 280 characters for a standard post on X.
A rule-based checker, made for captions
This checker uses a list of rules and known mistakes written by our team, not AI. It is tuned for social media, so it leaves hashtags, mentions and emojis alone, and it does not complain about an all-lowercase caption, which is often a deliberate style.
Rules cannot understand meaning, so the checker will not catch every error and may occasionally flag something you wrote on purpose. Treat each suggestion as a prompt to take a second look.
Frequently asked questions
Is the caption grammar checker free?
Yes. It is free to use with no sign-up and no usage limit.
Does it use AI?
No. It runs a set of hand-written rules in your browser, so your caption is never uploaded.
Why did it not catch a mistake?
The checker looks for common, well-defined errors. Grammar that depends on meaning or context is beyond simple rules, so always give your caption a final read.
Why does the platform matter?
Each platform has its own length limits and habits. For example, standard posts on X are limited to 280 characters, and links in Instagram captions are not clickable.
Will it change my hashtags or emojis?
No. Hashtags, mentions and emojis are left as they are, apart from flagging hashtags that an apostrophe would break.