Grammarly vs Spines
Which Writing AI tool is better in 2026?
Grammarly
AI writing assistant for individuals and teams.
Spines
AI-powered publishing platform that helps authors publish books fast
Side-by-side
Grammarly leads on both fronts — more capital raised ($1.2B) and a lower entry price than Spines.
| Metric | Grammarly | Spines |
|---|---|---|
| Taglinei | AI writing assistant for individuals and teams. | AI-powered publishing platform that helps authors publish books fast |
| Foundedi | 2009🏆 | 2021 |
| HQi | San Francisco, US | Boynton Beach, US |
| Employeesi | 1001-5000 | 11-50🏆 |
| Neuron scorei | 68🏆 | 57 |
| Total fundingi | $1.2B🏆 | $29M |
| Latest roundi | Growth · May 2025 | Series A |
| Valuationi | $13B🏆 | — |
| Cheapest paid plani | Pro (Annual) · $12/mo🏆 | Pricing not disclosed |
| Free plani | ✓ Free | ✓ |
| Free triali | ✓ | ✓ |
| Top tier pricei | Pro (Monthly) · $30/mo | Pricing not disclosed |
| Pricing summaryi | 6 published plans | Free |
| Categoriesi |
Capability matrix
Developer-facing capabilities and access signals for Grammarly and Spines.
| Capability | Grammarly | Spines |
|---|---|---|
| MCP support | ✗ | ✗ |
| Public API | ✗ | ✗ |
| Webhooks | ✗ | ✗ |
| OAuth 2.0 | ✗ | ✗ |
| SDK languages | 1 (JavaScript) | — |
| Free plan | ✓ | ✓ |
| Free trial | ✓ | ✓ |
| Verified | ✗ | ✗ |
| Active deal | ✓ | ✗ |
🟢 Strengths of Grammarly
- Has raised more capital ($1.2B vs $29M)
- Higher Neuron score (68 vs 57)
- Lower starting price ($12/mo)
- More mature (2009)
🔵 Strengths of Spines
- Newer company (2021)
Which should you choose?
Choose Grammarly if price matters most — it starts at Free · From $12/mo, which is friendlier for teams watching burn. Both AI Writing tools ship core features, so the cost delta often decides it for small teams and solo operators.
Choose Grammarly if you want the most established option — it has raised $1.2B, suggesting more runway for enterprise features, support, and long-term roadmap. For mission-critical workflows or larger teams, that stability often outweighs a lower monthly price.
💸 Deals
7-day free trial of Grammarly Premium
Try Grammarly Premium free for 7 days — AI writing assistant used by 30M+ daily.
Frequently asked questions
Grammarly vs Spines — which is better?
It depends on your priority. Grammarly has raised more capital and is the more established option; Spines has broader feature depth. See the side-by-side table above.
Is Grammarly cheaper than Spines?
Yes — Grammarly's cheapest paid plan is Pro (Annual) · $12/mo, while Spines's is Free.
Do Grammarly and Spines offer free plans?
Grammarly: Yes, has a free plan. Spines: Yes, has a free plan.
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