Arize AX vs Helicone 2026: Unlimited Seats and Evals Against Usage-Based Billing
Quick verdict: Arize AX is our overall pick for arize-ax vs helicone.
Arize AX charges $50/mo with unlimited users and unlimited evals; Helicone charges $79/mo with unlimited seats but usage-based pricing on top of the tier.
| Tool | Rating | Pricing | Best for |
|---|---|---|---|
| Arize AX Best overall Best for teams | 4.0/5 | Free $50/mo (AX Pro) | Arize AX is the cheapest paid step in the cluster at $50/mo, with a $0 Free tier (25K span… |
| Helicone Best free | 3.8/5 | Free $79/mo (Pro) | Helicone is the request-level observability and gateway layer priced per request: Hobby fr… |
Bottom line: Arize AX for a predictable flat fee that never scales with your team size, plus free open-source Phoenix if you want to go fully local. Helicone for the simplest possible integration and a gateway with caching, rate limits and fallbacks - but expect a usage-based line to appear on top of the $79. The two overlap least: Arize is a tracing and evaluation platform, Helicone is a proxy. Pick Langfuse for a middle price with self-hosting.
Pricing and details
Arize AX · 4.0/5
Free plan available · $50/mo (AX Pro)
Billed on signals, spans, ingestion volume and retention rather than seats - users and evals are unlimited on every tier; self-hosted deployment is Enterprise-only, while the open-source Phoenix platform is free and local
No published annual rate; a separate startup pricing track exists on the pricing page
Arize AX is the cheapest paid step in the cluster at $50/mo, with a $0 Free tier (25K spans, 1 GB, 15-day retention) and a free open-source sibling in Arize Phoenix for fully local tracing.
Score breakdown
Pros
- Unlimited users and unlimited evaluations on every tier, including the free one - the only cluster member that never charges for seats
- $50/mo is the cheapest paid step in the set, undercutting Braintrust Pro by 5x
- Arize Phoenix is a genuinely free, open-source, local-first platform for tracing and evaluation with no account required
- Session-level and multi-modal tracing (image, voice, PDF), agent trajectory visualizations and online/offline evals are unlimited on all tiers
Cons
- The free tier is narrow - 10 signals a month and 25K spans, so production volume will not fit
- Self-hosted deployment is Enterprise-only; the free local option is the separate Phoenix project, not AX itself
- SOC 2 Type II, SSO, audit logs, HIPAA and data-region choice start at Enterprise
Pricing verified 2026-10-03
Helicone · 3.8/5
Free plan available · $79/mo (Pro)
Requests are the billing unit and usage-based pricing applies on top of every paid tier; storage beyond 1 GB is usage-billed, and Helicone announced it has joined Mintlify
No published annual rate; published discounts are 50% off year one for startups under 2 years old and under $5M raised, org-size-based non-profit discounts, a $100 first-year credit for open-source companies and free plans for students
Helicone is the request-level observability and gateway layer priced per request: Hobby free with 10,000 requests a month, Pro at $79/mo, Team at $799/mo, and usage-based pricing on top.
Score breakdown
Pros
- The easiest adoption story in the cluster - a one-line integration, the clearest interface of the five, and no framework lock-in since it sits at the request layer
- Straightforward request-based pricing with a published calculator: 10K free requests, then usage-based billing on every paid tier
- Caching, rate limits, automatic fallbacks and a gateway ship in the same product, so observability and routing are one purchase
- Real discount programs: 50% off year one for startups under 2 years old and under $5M raised, org-size non-profit discounts, a $100 credit for open-source companies, free for students
Cons
- Narrowest scope: its own pricing page rates its tracing, UI, experiments and evaluation as limited or average against the other four
- 7-day retention on Hobby and only 1 month on Pro, with 3 months on the $799 Team plan
- Ingest ceilings are low by comparison - 10 logs/min on Hobby against 1,000 on Pro and 30,000 on Enterprise
Pricing verified 2026-10-03
Frequently asked questions
Which is better overall, Arize AX or Helicone?
Arize AX is our overall pick (4.0/5 vs 3.8/5). Arize AX charges $50/mo with unlimited users and unlimited evals; Helicone charges $79/mo with unlimited seats but usage-based pricing on top of the tier.
Do Arize AX and Helicone offer free plans?
Arize AX and Helicone have a free tier. Arize AX paid plans start at $50/mo (AX Pro); Helicone paid plans start at $79/mo (Pro).
What does Arize AX cost?
$50/mo (AX Pro) — Billed on signals, spans, ingestion volume and retention rather than seats - users and evals are unlimited on every tier; self-hosted deployment is Enterprise-only, while the open-source Phoenix platform is free and local. Prices were last verified on 2026-10-03.