Grok
Free tier available
- Free$0
- X Premium$8/mo
- X Premium+$40/mo

Grok
Our pickGrammarly
Tier-list head-to-head. Grammarly takes the A-tier slot — here's the breakdown.
Spec sheet
| Tier | B-tier | A-tierwin |
| Overall score | 7.5 / 10 | 8.0 / 10win |
| Free tier | Yes | Yes |
| Starting price | $0 | $0 |
| Best for | People who live on X/Twitter and want an AI that can tap into that data in real-time. | Non-native English speakers, professionals who write lots of emails, and anyone who wants a passive grammar… |
| Last reviewed | 2026-05-19 | 2026-03-26 |
Head-to-head
Rated 1-10 on the same rubric across all 130 tools we cover.
What you'll pay
Look past the headline number -- entry-tier limits drive most cost surprises.
Free tier available
Free tier available
Grok 4.20 benchmarks — Grammarly has no published benchmarks
| Benchmark | Description | Score |
|---|---|---|
| MMLU | Knowledge across 57 subjects | 88.5% |
| GPQA Diamond | Graduate-level science questions | 85% |
| HumanEval | Python code generation | 90% |
| Humanity's Last Exam | Frontier difficulty questions | 50.7% |
The decision
Use-case anchors and category strengths, side by side.
People who live on X/Twitter and want an AI that can tap into that data in real-time. Also good for users who find mainstream chatbots too sanitized and want something with more personality.
Visit GrokNon-native English speakers, professionals who write lots of emails, and anyone who wants a passive grammar net running in the background. It catches things you'd miss.
Visit GrammarlyBottom line
Grammarly edges out Grok by 0.5 points (8.0 vs 7.5) -- a A-tier vs B-tier split that's narrow but real. Not a blowout; both belong on a shortlist. The score gap shows up most clearly in the categories that matter for Grammarly's strengths, so if those categories are your priority, the lead translates.
Pricing-wise, both tools have a free tier (Grok starts $0, Grammarly starts $0), so you can test either without committing. Compare what each free tier actually unlocks -- usage caps, model access, and feature gates differ a lot more than the headline price suggests, especially as both vendors have tightened limits in 2026.
By use case: pick Grok when people who live on x/twitter and want an ai that can tap into that data in real-time. Pick Grammarly when non-native english speakers, professionals who write lots of emails, and anyone who wants a passive grammar net running in the background. The two tools aren't fighting for the same person -- they're aiming at adjacent jobs that occasionally overlap. If you're squarely in Grammarly's lane, the tier-list ranking and the use-case fit point the same direction; if you're in Grok's lane, the score gap matters less than the fit.
Bottom line: Grammarly is the safer default for most readers, but Grok is competitive enough that the tie-breaker is your specific workload, not the spec sheet.
Keep digging
Full Grok review
Tier B · 7.5/10
Full Grammarly review
Tier A · 8.0/10
Grok alternatives
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Grammarly alternatives
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Built from our daily AI-tool sweep, last touched May 19, 2026. Honest tier-list reviews — no affiliate-link pieces disguised as advice. See the rubric or how we review.