AI21 Labs vs Grammarly vs Underfiction vs Writesonic
| Attribute | ||||
|---|---|---|---|---|
| Category | AI & Automation | Content & Writing | Content & Writing | Content & Writing |
| Pricing | Free tier | Free tier | Free tier | Free tier |
| Starting price | — | $12/month | $0.01/month | $12/month |
| Free tier | Yes | Yes | Yes | Yes |
| Free trial | Yes | Yes (7d) | Yes | No |
| Deployment | — | — | — | Cloud |
| API available | Unknown | Yes | Unknown | Unknown |
| Platforms | — | — | — | — |
| Certifications | — | 1 | — | — |
| Integrations | — | — | — | — |
| Company | Founded 2017 | Founded 2009 | — | — |
| Feature attributes | ||||
| Sso Saml | — Unknown | ✓ Yes | — Unknown | — Unknown |
| Rbac | — Unknown | ✓ Yes | — Unknown | — Unknown |
| Mobile App | — Unknown | — Unknown | — Unknown | — Unknown |
| Webhooks | — Unknown | — Unknown | — Unknown | — Unknown |
| Data Export | — Unknown | — Unknown | — Unknown | — Unknown |
| Ai Generation | — Unknown | ✓ Yes | — Unknown | — Unknown |
| Grammar Check | — Unknown | ✓ Yes | — Unknown | — Unknown |
| Plagiarism Check | — Unknown | ✓ Yes | — Unknown | — Unknown |
| Brand Voice | — Unknown | ✓ Yes | — Unknown | — Unknown |
| Browser Extension | — Unknown | ✓ Yes | — Unknown | — Unknown |
Also consider
Unknown values show as “Unknown”/“—”. Nothing is inferred — see each tool page for sources.