Langfuse vs Opik
Both are observability & tracing tools. Here is how they actually differ on price, billing model and deployment.
Langfuse
The open-source LLM observability default. Free, MIT-licensed, genuinely feature-complete when self-hosted - now a ClickHouse subsidiary after its January 2026 acquisition.
Opik
Comet's open-source LLM observability and eval platform - the cheapest paid cloud in the category at $19/mo, and the most permissive OSS license. Apache-2.0, full feature set self-hosted, and the fastest-growing project of its peers.
| Langfuse | Opik | |
|---|---|---|
| Category | Observability & Tracing | Observability & Tracing |
| Our rating | 5/5 | 5/5 |
| Starting price | $29/mo | $19/mo |
| Billing meter | event | span |
| Free plan | Yes | Yes |
| Free self-hosting | Yes, free | Yes, free |
| Best for | Teams that want an open-source observability platform they can self-host without losing features | Teams that want a genuinely feature-complete open-source observability platform, or the cheapest managed cloud, without a license or feature-gate catch |
Our verdict on Langfuse
The open-source default for good reason - self-hosting is free and doesn't cripple the product, and it's dramatically cheaper than LangSmith at scale. The catch is operational, not commercial - the v3 architecture is four services now, and the migration bites. If you have the ops capacity, nothing else in the category gives you this much for free.
Full Langfuse review →Our verdict on Opik
The most honest open-source deal in the category - Apache-2.0, the full feature set self-hosted with no gates, and if you want managed, the cheapest cloud tier here at $19/mo. It is also the fastest-growing project of its peers, which tells you the market agrees. The one real watch-out is per-seat pricing - it scales poorly as your team grows, and a few large-project users report UI slowdown.
Full Opik review →Frequently Asked Questions
What is the main difference between Langfuse and Opik?
Langfuse: Teams that want an open-source observability platform they can self-host without losing features Opik: Teams that want a genuinely feature-complete open-source observability platform, or the cheapest managed cloud, without a license or feature-gate catch Both sit in Observability & Tracing, so the decision usually comes down to billing model and deployment rather than raw capability.
Which is cheaper, Langfuse or Opik?
It depends entirely on your workload shape, because they meter differently - Langfuse bills on event and Opik bills on span. Published starting prices are $29/mo and $19/mo respectively, but those numbers are not comparable until you apply them to the same traffic. Use our cost calculator to model both against your own request volume and span count.
Can I self-host Langfuse or Opik?
Langfuse: Yes, free. Opik: Yes, free. Free self-hosting means no licence fee, not no cost - you still own the infrastructure, upgrades and on-call.