Grammar Checker API

Grammar Checker API — Grammar + style check in 4 modes (neutral, business, academic, casual).

What you get

• POST /v1/grammar/check — primary endpoint.
• X-API-Key authentication, per-key rate limits, audit log.
• OpenRouter-backed where AI is involved — no model keys to manage on your side.
• Interactive Swagger docs at api-grammar-check.knowlez.com/docs.

Plans

• Starter — $9/mo · 3,000 ops included · $0.002/op overage.
• Pro — $29/mo · 30,000 ops included · $0.001/op overage.