Helicone vs LangSmith
Open-source LLM observability — 1-line integration via proxy
vs. LLM observability, testing & evaluation — by LangChain
Pricing tiers
Helicone
Hobby (Free)
10,000 requests/month. 7-day retention. 1 seat. Basic monitoring.
Free
Startup Discount
<2 years, <$5M funding: 50% off first year.
$0 base (usage-based)
Self-Hosted (OSS)
MIT-licensed. Run Helicone yourself for free.
$0 base (usage-based)
Pro
$79/month. 10k free + usage-based. Unlimited seats. Alerts, reports, HQL query language. 1-month retention.
$79/mo
Team
$799/month. 5 orgs, SOC-2 + HIPAA compliance, dedicated Slack, 3-month retention.
$799/mo
Enterprise
Custom MSA, SAML SSO, on-prem deploy, bulk discounts, forever retention.
Custom
LangSmith
Developer (Free)
Free forever. 5,000 traces/month. 14-day retention. 1 seat. Basic evaluations.
Free
Plus
$39/seat/month. 10k base traces included ($2.50 per 1k overage). Full evaluations, custom dashboards, email support.
$39/mo
Enterprise
Custom. Self-host option, SSO, custom retention, dedicated support.
Custom
Free-tier quotas head-to-head
Comparing hobby on Helicone vs developer on LangSmith.
| Metric | Helicone | LangSmith |
|---|---|---|
| No overlapping quota metrics for these tiers. | ||
Features
Helicone · 16 features
- Alerts — Thresholds on error rate, latency, cost, usage. Pro+.
- Async Logging — Log AFTER the LLM call via SDK — zero added latency.
- Cost Tracking — Automatic cost calculation per call by provider/model.
- Dashboard — Request tables, aggregate metrics, cost breakdowns.
- Evaluators — LLM-as-judge + custom evaluators on runs.
- Experiments — A/B test different models/prompts.
- HQL (SQL over traces) — Query your logged data with SQL. Pro+.
- PII Redaction — Automatically scrub emails, credit cards, etc. from logs.
- Prompt Caching — Cache identical requests → save money.
- Prompts & Versions — Store + version + A/B test prompts.
- Proxy Mode — 1-line integration via base URL swap. Captures all requests.
- Rate Limiting — Per-user + per-key rate limit policies.
- Reports — Scheduled email reports with KPIs.
- Self-Hosting — Docker + k8s deployment.
- Sessions — Group related calls (chat sessions, agent runs).
- User Metrics — Per-user cost + usage segmentation.
LangSmith · 14 features
- Alerts — Threshold alerts on latency, cost, eval metrics.
- Annotation Queues — Human-review workflows for trace quality rating.
- Custom Dashboards — Aggregate metrics dashboards per project/tag.
- Datasets — Collect examples → use as eval sets or training data.
- Evaluations — LLM-as-judge, embedding similarity, custom Python evaluators, offline batch eval…
- LangChain Integration — Auto-trace any LangChain/LangGraph run with env var.
- LangGraph Integration — First-class trace + eval for LangGraph agents.
- LLM Tracing — Automatic trace every LLM call + tool call + chain step.
- OpenTelemetry Export — Export traces as OTLP to Datadog/Honeycomb/etc.
- Playground — Test prompts + models inline before deploying.
- Prompt Canvas — Visual prompt editor with live test + eval.
- Prompt Hub — Public + private prompt library with versioning.
- Self-Hosted (Enterprise) — Docker + k8s deployment in your infra.
- Threads + Sessions — Group traces into conversational sessions.
Developer interfaces
| Kind | Helicone | LangSmith |
|---|---|---|
| CLI | Helicone CLI | LangSmith CLI |
| SDK | helicone (npm), helicone-python | langsmith-js, langsmith-python |
| REST | Async Logging API, Helicone Proxy, Query API (HQL) | LangSmith REST API |
| MCP | — | LangSmith MCP |
| OTHER | Helicone Dashboard, Webhooks | LangSmith Dashboard |
Staxly is an independent catalog of developer platforms. Outbound links to Helicone and LangSmith are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
Want this comparison in your AI agent's context? Install the free Staxly MCP server.