Our verdict: The most invisible AI tool on this list — and that's its superpower. Free tier catches the embarrassing stuff; Premium adds tone and style.
Best for
Catching errors and fixing tone in everyday writing
Pricing
Free tier available · Premium from ~$12/mo
Last tested
Aug 30, 2026
What we like
- Works everywhere: browser, Word, email, Slack
- Free tier catches real errors
- Tone rewrites actually improve how you sound
What to watch
- Suggestions can be annoyingly aggressive
- Premium price is high for what it adds
- Privacy-conscious teams may not want it on everything
Grammarly is the rare AI tool that’s been quietly working for years. It sits in your browser and catches typos, grammar slips, and awkward phrasing in real time — before you hit send.
What it’s actually good at
- Error catching. The free tier alone prevents most embarrassing mistakes.
- Tone adjustments. “Make this sound more confident/softer” works surprisingly well.
- Pervasiveness. It’s wherever you type, which means you don’t have to remember to use it.
Where it falls short
- Over-suggesting. Its suggestions can flatten your voice; you’ll learn to ignore some.
- Cost. The free tier is genuinely useful; Premium’s extras are nice-to-have.
Who is it for?
Anyone who writes emails, messages, or documents in English. Install the free browser extension today — it’s the closest thing to a free writing upgrade.
Bottom line: the lowest-effort AI win on this list.
Prices and features change fast — we last verified this entry on Aug 30, 2026.