TokenZero vs Langfuse
Langfuse is tracing SDKs, prompt management, evaluations and cost dashboards. The matrix below says what each product is and how it bills; the only numbers are TokenZero's own measurements and prices.
TokenZero and Langfuse differ in kind: Langfuse is LLM observability and evals; TokenZero is a BYOK gateway whose engines reduce the provider bill and sign a receipt per call. Measured overhead is 1.52 ms p50; the cascade holds a 99.8% parity floor. On 100,000 gpt-6.1-sol calls, prefix caching saves $285 a month, $242 net of the 15% fee.
· Source: Langfuse documentation at https://langfuse.com/pricing read 2026-10-26; TokenZero overhead from /benchmarks; prices from table 2026-10-26
At a glance
- Compared with
- Langfuse (LLM observability and evals)
- TokenZero overhead
- 1.52 ms p50 / 3.42 ms p95 (measured, /benchmarks)
- BYOK
- TokenZero: always · Langfuse: not a proxy (SDK tracing)
- Receipts
- TokenZero: signed per call · Langfuse: none
- Billing
- TokenZero: 15% of verified savings · Langfuse: free tier, then event-volume plans
- Reference saving (gpt-6.1-sol, 100k calls)
- $285/month from prefix caching (computed)
- Net after 15% fee
- $242/month (computed)
- Parity floor
- 99.8%
- Free tier
- $500/month routed
- Vendor page read
- 2026-10-26
TokenZero vs Langfuse: what each one is (vendor page read 2026-10-26)
| Dimension | TokenZero | Langfuse |
|---|---|---|
| Category | BYOK savings gateway | LLM observability and evals |
| Hosting | hosted | hosted; self-hostable |
| Bring your own key | always; keys pass through and are never stored | not a proxy (SDK tracing) |
| Open source | CLI, MCP server, audit core and GitHub Action Apache-2.0; gateway hosted | MIT core |
| How it bills | free up to $500/month routed; then 15% of verified savings, 3x-ROI-or-$0, capped plans | free tier, then event-volume plans |
| Caching | prompt-cache formatting + exact and semantic response cache | none (not a proxy) |
| Routing | cascade to the cheaper sibling inside one provider, 99.8% parity floor, advisory by default | none |
| Savings receipts | Ed25519-signed per call, hash-chained, public key published | none |
| Gateway overhead | 1.52 ms p50 / 3.42 ms p95 (measured, /benchmarks) | not measured by TokenZero |
| Data retention | metadata only; ZDR mode available | see vendor docs |
| Net saving, 100k gpt-6.1-sol calls/month (prefix caching only) | $242 after fee | — |
What you keep when you move from Langfuse
your tracing: TokenZero is transport-level, Langfuse SDK calls keep working.
- TokenZero changes the bill; Langfuse explains it. The receipt id in X-TokenZero-Request-Id attaches to a trace.
- No prompt or completion storage on the TokenZero side.
The change
OPENAI_BASE_URL=https://tokenzero.sh/v1
ANTHROPIC_BASE_URL=https://tokenzero.sh
# keep your provider keys exactly as they areThen npx -y @tokenzero/cli doctor to confirm the gateway, signer and pricing table, and see the switch guide.
Questions people ask
What is the difference between TokenZero and Langfuse?
Langfuse is tracing SDKs, prompt management, evaluations and cost dashboards. TokenZero is a BYOK gateway: you keep your tracing: TokenZero is transport-level, Langfuse SDK calls keep working, and every call comes back with a signed receipt. TokenZero changes the bill; Langfuse explains it. The receipt id in X-TokenZero-Request-Id attaches to a trace.
What does switching from Langfuse to TokenZero save?
It depends on your prompts; on the reference workload (100,000 calls of 2,000 input with a 1,500-token static prefix and 300 output on gpt-6.1-sol, table 2026-10-26) prefix caching alone cuts $700 to $415 a month, $285 saved and $242 net after the 15% fee; exact-cache hits and cascade routing add to that. The receipts show the real figure.
Can I keep Langfuse and add TokenZero?
Yes. Langfuse is not a transport-level proxy, so it keeps working unchanged; TokenZero changes only the base URL your SDK calls.
How is the 15% fee computed?
On verified savings only: list-price baseline minus provider-reported actual cost, per signed receipt. A cycle whose savings are below 3x the fee is billed $0; Pro Cap and Scale Cap add monthly ceilings. The first $500 of routed spend each month is free.