The Langfuse Free Tier Explained in 2026 - Limits, Cap and When to Leave

“Is Langfuse free” has a more interesting answer than yes or no. There are two free Langfuse options, they work completely differently, and picking the wrong one for your situation costs you either money or a weekend of ops. Let me explain what each one actually gives you, what the cap really counts, and when to jump.

The two free tiers are not the same

This trips people up constantly, so it goes first.

Option one is the Hobby cloud tier. It is $0, hosted by Langfuse, and capped. You get 50k billable units a month as a hard limit, 30-day retention, and 2 users. No infrastructure to run, no ops. When you hit the cap, you stop.

Option two is the free self-host. The self-hosted build is MIT-licensed and free, with no unit cap. You run it on your own infrastructure. The per-trace cost disappears entirely - you pay only for the servers.

Same product, two very different deals. Full detail is on the Langfuse page.

Free option	Cost	Volume cap	Retention	Users	Ops
Hobby (cloud)	$0	50k units/mo, hard	30 days	2	None
Self-host	$0	None	You configure	Unlimited	You run it

What “50k billable units” actually counts

The number 50k sounds generous until you understand the unit. A billable unit is one trace, one observation, or one score - not one request. A single user request in a real app often produces a trace with several observations (the spans for each LLM call and tool step) and a couple of eval scores on top. That one interaction can consume five, ten or more units.

So the practical read is this. 50k units does not mean 50k requests - for a multi-step agent it can mean far fewer. A simple single-call app will stretch the cap a long way. A verbose agent that traces every tool call and scores every output will reach 50k faster than the round number implies. Count your units per request before you assume Hobby covers your traffic. I broke the full quota math down in the Langfuse pricing guide.

And remember the Hobby cap is hard. It is not an overage rate. You do not pay a little more past 50k - you are simply done until next month or until you upgrade.

When to leave the free cloud tier

Three signals tell you the Hobby tier has run its course.

You need more than 2 users. This is the most common one. The moment a second teammate needs their own login, the Core tier at $29/mo unlocks unlimited users and bumps you to 100k units with $8 per additional 100k.

You are hitting 50k units. If you are bumping the hard cap monthly, you either pay for Core or move to self-host. Which one depends on the next signal.

Your volume is high enough that even paid cloud stings. This is where self-host wins decisively. At 1M events a month, managed Langfuse runs about $101/mo, and self-host removes the per-trace cost entirely. If you have the ops capacity to run the self-host stack, it is the cheapest observability you can get - the software is free. The honest catch is that Langfuse v3 needs four services - Postgres, ClickHouse, Redis and S3-compatible storage - and the migration is where self-hosters get stuck. Free software, real ops time. See how to self-host Langfuse.

When Opik’s free tier beats Langfuse

Langfuse is not the only strong free tier, and for some teams Opik is the better free deal. It comes down to what you are short on.

On the cloud, the trade is volume versus seats. Langfuse Hobby gives you 50k units but only 2 users and 30-day retention. Opik’s Free Cloud gives 25k spans but up to 10 members and 60-day retention. So if you have a small team that needs several logins on a free plan, Opik’s 10 members beats Langfuse’s 2 outright - even though the raw volume is lower. If you are a solo builder pushing volume, Langfuse’s 50k wins.

On self-host, Opik has the cleaner license. Langfuse self-host is MIT with three features gated. Opik’s self-host is Apache-2.0 with the full feature set and no gates at all - unlimited spans, members and retention. If “open source with zero asterisks” matters to you, Opik is the more permissive choice. I compared them head to head in Opik vs Langfuse.

So which free tier should you start on?

• Solo builder, single app, want zero ops - Langfuse Hobby. The 50k units stretch furthest for one person.
• Small team that needs several free logins - Opik Free Cloud, for the 10 members and 60-day retention.
• You have ops capacity and want no caps - self-host Langfuse under MIT, or Opik under Apache-2.0 if you want zero feature gates.
• You have outgrown free volume but not ops - Langfuse Core at $29/mo for unlimited users, or Opik Pro at $19/mo for 100k spans.

The one mistake to avoid is treating the two Langfuse free tiers as interchangeable. Hobby is capped and hosted. Self-host is uncapped and yours to run. Know which problem you have before you pick. For the wider view, see the best free LLM observability tools and Langfuse alternatives.

Every price and limit here was read from each vendor’s own pages and verified on 26 July 2026. This category ships breaking changes monthly, so we re-verify every 30 days.