Head to head
| Metric | Braintrust | Langfuse | LangSmith | Arize Phoenix |
|---|---|---|---|---|
| Stars | n/a | 37.3k | n/a | 12.2k |
| Weekly downloads | 3.2M | 7.4M | 21.2M | 117k |
| Download growth | +63% | +32% | +19% | -4% |
| Popularity score | 80/100 | 84/100 | 90/100 | 68/100 |
| Forks | n/a | 4.2k | n/a | 1.3k |
| Open issues | n/a | 1.2k | n/a | 1.2k |
| Last commit | n/a | today | n/a | 4d ago |
| Latest version | 3.44.0 | 5.2.0Nov 5, 2026 | 0.14.17Nov 2, 2026 | 21.0.0Oct 30, 2026 |
| First released | n/a | 2023 | n/a | 2022 |
| Signals | Rising | TrendingPopular | Popular | None |
| Listed in | AI & Machine Learning › LLM Observability & Evals | AI & Machine Learning › LLM Observability & Evals | AI & Machine Learning › LLM Observability & Evals | AI & Machine Learning › LLM Observability & Evals |
Weekly downloads over time
Hover for exact values; switch to log scale for tools of very different sizes. Not shown (no comparable download data): Braintrust.
- Langfuse
- LangSmith
- Arize Phoenix