The Result
A3M Router just topped the RouterArena leaderboard at 76.43 — the first open-source project ever to rank #1.
| Rank | Router | Score | Cost/1K |
|---|---|---|---|
| 🥇 | A3M Router | 76.43 | $0.047 |
| 🥈 | Sqwish | 75.27 | $0.18 |
| 🥉 | Azure-Model-Router (Microsoft) | 71.87 | $0.22 |
| 4 | GPT-5 (OpenAI) | 64.32 | $10.02 |
| 5 | RouteLLM (Berkeley) | 48.07 | $0.27 |
A3M is also the cheapest router on the leaderboard — 3.8x cheaper than #2 and 213x cheaper than GPT-5.
Why It Matters
Every other router does sequential model selection (try one, if it fails try the next). A3M runs multiple providers in parallel and scores each response by confidence. This is why it achieves the best accuracy at the lowest cost.
RouterArena (arXiv:2510.00202) evaluates 19 routers on 8,400 queries across 9 domains with 5 quality metrics. The evaluation was fully automated and reproducible.
Try It
npx a3m-router route "Explain quantum computing"
GitHub: https://github.com/Das-rebel/a3m-router
Benchmark: https://das-rebel.github.io/a3m-router/benchmark
