Softwr

AI · head to head

Arize AI vs Railway

Arize AI logo

Arize AI

AI

AI engineering platform for observability and evaluation of agents and LLM apps

From
Free
Rated
-
Full reviewWebsite
Railway logo

Railway

Cloud

Ship software instantly

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Arize AI the free plan caps trace spans at 25,000 per month with only 15 days of retention.; Railway plan fees are usage credits rather than allowances, so the $5 Hobby and $20 Pro fees are spent on compute and anything beyond is billed on top
  • They diverge on capability: Arize AI covers End-to-end tracing, Railway covers Git integration.

Where they differ

Only the attributes on which Arize AI and Railway actually diverge.

Attributes where Arize AI and Railway differ
AttributeArize AIRailway
Pricing modelfreemiumusage-based
Platformsweb, apiWeb, Api, Docker
CategoryAICloud
FoundedUnknown2021

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in Arize AI

  • End-to-end tracing
  • Evaluation framework
  • Prompt testing and improvement
  • Alyx AI engineering agent
  • Custom dashboards
  • Data warehouse integrations

Only in Railway

  • Git integration
  • Zero-config deployment
  • PostgreSQL
  • MySQL
  • Redis
  • Environment variables
  • Custom domains
  • Monitoring

What people use each for

The jobs each tool is most often brought in to do.

Arize AI

  • Tracing and debugging production AI agentsnot Railway
  • Running large-scale evaluations across traces and sessionsnot Railway
  • Improving prompts before production rolloutnot Railway
  • Storing and querying GenAI traces alongside a data warehousenot Railway

Railway

  • Deploying applications and databases without managing serversnot Arize AI
  • Running preview environments and services straight from a repositorynot Arize AI

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Arize AI

  • The free plan caps trace spans at 25,000 per month with only 15 days of retention.
  • Self-hosted deployment and Data Fabric integration are restricted to the custom-priced Enterprise tier.
  • Pricing beyond the $50/month Pro plan requires a custom quote, making cost planning less transparent at scale.
  • Advanced compliance features like HIPAA are only available on Enterprise.

Railway

  • Plan fees are usage credits rather than allowances, so the $5 Hobby and $20 Pro fees are spent on compute and anything beyond is billed on top
  • The free plan carries $1 of monthly credit and caps a service at 1 vCPU and 0.5 GB
  • Compute is metered per second for both memory and CPU, so cost tracks uptime rather than traffic and an idle service still bills
  • Egress is $0.05 per GB on top of compute
  • The Pro fee is per workspace rather than per user or per project

Pricing, plan by plan

Arize AI

Free
  • AX FreeFree
    • 25k trace spans/month
    • 1 GB storage/month
    • 15-day retention
  • AX Pro$50/month
    • 50k trace spans/month
    • 10 GB storage/month
    • 30-day retention
  • AX Enterprise$undefined/mo
    • Custom trace spans, storage, and retention
    • SaaS or self-hosted deployment
    • Managed agents and Data Fabric

Railway

Free
  • FreeFree
    • $5 credit/month
    • Community support
    • Unlimited projects
  • Pro$20/month
    • Private repos
    • Priority support
    • Advanced monitoring

Which should you pick?

Choose Arize AI if

  • You need end-to-end tracing.
  • You want to start without paying.
  • You work on web, api.
  • You also want evaluation framework.
Arize AI review

Choose Railway if

  • You need git integration.
  • You want to start without paying.
  • You work on Web, Api, Docker.
  • You also want zero-config deployment.
Railway review

Questions people ask

Is Arize AI or Railway better?
Neither clearly leads. Arize AI starts at Free and Railway at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Arize AI or Railway?
Arize AI starts at Free and Railway at Free.
Does Arize AI or Railway run on more platforms?
Arize AI runs on web, api. Railway runs on Web, Api, Docker.
Can I use Arize AI for free?
Both have a free tier, so you can try either at no cost before committing.
What is Arize AI best used for?
Arize AI is most often used for tracing and debugging production ai agents, running large-scale evaluations across traces and sessions, improving prompts before production rollout, storing and querying genai traces alongside a data warehouse. Of those, tracing and debugging production ai agents and running large-scale evaluations across traces and sessions are not what Railway is typically brought in for.
What can Arize AI do that Railway cannot?
Arize AI covers End-to-end tracing, Evaluation framework, Prompt testing and improvement, Alyx AI engineering agent. Railway covers Git integration, Zero-config deployment, PostgreSQL, MySQL.

Answered from the vendors’ own pages

Arize AI: What does Arize AX cost?

Arize AX offers a free plan, a Pro plan at $50/month, and a custom-priced Enterprise plan, with pricing based on trace spans, storage, and retention needs.

Source
Railway: How much does Railway cost?

Railway's Hobby plan is $5 per month and includes $5 of monthly usage credit. Pro is $20 per month per workspace with $20 of credit included. Enterprise is quoted. Usage beyond the included credit is billed per second.

Source
Arize AI: Is there a free plan, and what are its limits?

The AX Free plan includes 25,000 trace spans and 1 GB of storage per month with 15-day retention, plus unlimited users, evaluations, and experiments.

Source
Railway: Does Railway have a free tier?

Yes, two. A one-time Free Trial gives $5 of credit valid for 30 days, and an ongoing Free plan includes $1 per month with 1 vCPU and 0.5 GB per service, 1 replica and 3 days of log history.

Source
Arize AI: What deployment options are available?

Free and Pro plans are SaaS-only, while Enterprise customers can choose SaaS or self-hosted deployment with custom SLAs.

Source
Railway: What are Railway's resource limits per plan?

The Free plan allows 1 vCPU and 0.5 GB per service with 1 replica. Hobby raises that to 48 vCPU and 48 GB with 6 replicas. Pro allows 1,000 vCPU and 1 TB per service with 42 replicas and 30 days of log history.

Source
Railway: How does Railway bill usage above the included credit?

Railway charges memory at $0.00000386 per GB per second and CPU at $0.00000772 per vCPU per second, with storage volumes at $0.00000006 per GB per second, plus separate egress and object storage fees.

Source
Share

Related pages

More on Arize AI

More on Railway

Keep looking

Other head to heads