aigrammarproofreading

AI Caption Grammar Checker — Free Tool

Fix the spelling, grammar and punctuation in a caption without losing your voice, your emoji, or your line breaks.

Real examples

Actual output from the assistant, per platform.

Brief
Their going to love this weeks episode, its our best one yet
They're going to love this week's episode — it's our best one yet

Features

  • Corrects spelling, grammar and punctuation only
  • Leaves your voice, emoji, hashtags and line breaks alone
  • Returns the caption unchanged when it is already correct
  • Runs at a low temperature so it cannot drift into rewriting

Input

Paste the caption to check

Free to use

3 generations a day, no account — then 50 free generations/month

How it works

  1. Paste the caption you already have. These three tools work on your draft rather than on a brief — your wording is the input, not a topic.
  2. Press Generate. It runs right here — no account, no card, three times a day.
  3. Need more? A free account raises the limit to 50 AI generations a month.
  4. It also moves generation into the composer, next to your channels and schedule — several variants per platform, then edit and schedule without leaving the page.

What you get free

Three generations a day on this page, with no account at all. Signing up is free and raises it: the Free plan includes 50 AI generations a month, Pro includes 300 and Business includes 1000 — and you can buy credits on any plan if you run out.

The reason to sign in isn't the limit, it's the workflow: generations happen where your drafts, channels, and schedule already are, so you go from brief to scheduled post without copying text between tabs. This page gives you one variant; the composer gives you several, plus improve, shorten, expand, and tone.

Getting better output

  • Paste the whole thing. Half a caption gives it half the context, and it will fill the gap with something you didn't write.
  • Use the per-platform page, not the general one. The platform changes the length, the register, and in some cases the rules the result has to obey.
  • Run it more than once. Each run is independent, and the second attempt on a sharper brief usually beats editing the first.
  • Treat it as a first draft. The fastest workflow is generate, then change one line — not generate and paste.

Frequently asked questions

Will it rewrite my caption?

No. It runs deliberately cold and is told to change nothing but errors — your wording, emoji, hashtags and line breaks come back as you typed them. If it is already correct you get it back unchanged. Rewriting is a separate tool.

Which platforms does it work for?

The 8 covered here — Instagram, LinkedIn, X (Twitter), Facebook, YouTube, TikTok, Threads and Pinterest — each with its own page and its own worked example. Pick the platform you are posting to rather than the general version; the differences between them are the whole point.

Do I need an account?

No — you get 3 free generations a day right on this page, no signup. A free account lifts the limit: the Free plan includes 50 AI generations a month, Pro includes 300 and Business includes 1000, or you can buy credits on any plan.