# FreeAgent API vs Invoice Ninja API (slim)

> FreeAgent API has a score of 57.6 (C) against Invoice Ninja API's 52.4 (D). Both do accounting invoices. The largest gap is reliability, 49 points. Category scores, facts, verdicts and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/freeagent-vs-invoice-ninja.md (~1,550 tokens) · this version ~330 tokens · JSON https://www.anchorterminal.com/compare/freeagent-vs-invoice-ninja.json · canonical https://www.anchorterminal.com/compare/freeagent-vs-invoice-ninja
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-04

FreeAgent API has a score of 57.6 (C) against Invoice Ninja API's 52.4 (D). Both do accounting invoices. The largest gap is reliability, 49 points.

- FreeAgent API: C 57.6, rank #291 of 452 · https://www.anchorterminal.com/tools/freeagent.min.md
- Invoice Ninja API: D 52.4, rank #342 of 452 · https://www.anchorterminal.com/tools/invoice-ninja.min.md
- Pick FreeAgent API for reliability (+49), transparency & trust (+13). Pick Invoice Ninja API for schema & documentation (+16), agent ergonomics (+5), payments & pricing (+5), maintenance & community (+23).

| Category | FreeAgent API | Invoice Ninja API |
| --- | --- | --- |
| Reliability (16%) | 85 | 36 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 50 | 66 |
| Agent ergonomics (13%) | 55 | 60 |
| Security & auth (14%) | 44 | 48 |
| Payments & pricing (10%) | 30 | 35 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 60 | 83 |
| Transparency & trust (7%) | 78 | 65 |