Kong Reviews
Kong Reviews

LLM observability and gateways services compared: free tiers and pricing

10 llm observability and gateways services, each with its free tier and lowest paid price as read from its pricing page.

ServiceFree tierLowest paid priceChecked
BraintrustFree: $0/mo with $10 of credits, 1 GB and 10K scores includedPro $249/mo with $100 of credits2026-10-23
BrowserbaseFree: $0/mo, 3 agent runs and $5 in model tokensDeveloper $20/mo; Startup $99/mo2026-10-23
HeliconeFree: 10,000 requests/monthPro $79/mo (7-day trial)2026-10-23
LangfuseHobby: free, 50K units/monthCore $29/mo (100K units, then $8 per 100K)2026-10-23
LangSmithDeveloper: $0 for 1 seat, 5K traces/monthPlus $39 per seat per month (10K traces included)2026-10-23
LaunchDarkly5K AI runs a month$5 per additional 1K runs2026-10-23
OpenRouterFree: 25+ free models, 4 free providersPay-as-you-go: model list price plus a 5.5% fee on credit purchases2026-10-23
PortkeyFree forever: 10K recorded logs/monthProduction $49/mo (100K logs), +$9 per extra 100K2026-10-23
PostHog100,000 events/month$0.00035 per event2026-10-23
Sentry—$40 per active contributor per month2026-10-23

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