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Arize AI vs Writer

Arize AI logo

Arize AI

AI

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

From
Free
Rated
-
Full reviewWebsite
Writer logo

Writer

AI

Full-stack generative AI platform for enterprise content and agents

From
On request
Rated
-
Full reviewWebsite

The short version

  • Only Arize AI has a free tier, so it costs nothing to try first.
  • Each has a real cost: Arize AI the free plan caps trace spans at 25,000 per month with only 15 days of retention.; Writer pricing is not publicly disclosed and requires a sales conversation, unlike consumer AI writing tools.
  • They diverge on capability: Arize AI covers End-to-end tracing, Writer covers Palmyra LLMs.
  • Prices and features above were last checked on 29 August 2026.

Where they differ

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

Attributes where Arize AI and Writer differ
AttributeArize AIWriter
Starting priceFreeOn request
Pricing modelfreemiumquote
Free tierYesNo
FoundedUnknown2020

Identical on both: platforms (web, api), user rating (Not yet rated), category (AI).

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 Writer

  • Palmyra LLMs
  • Knowledge Graph
  • No-code agent builder
  • Brand compliance
  • AI writing assistant
  • Enterprise security controls

What people use each for

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

Arize AI

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

Writer

  • Enterprise marketing content generationnot Arize AI
  • AI-powered knowledge assistants grounded in company datanot Arize AI
  • Building custom generative AI agents without codenot Arize AI
  • Brand and compliance-consistent copywriting at scalenot 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.

Writer

  • Pricing is not publicly disclosed and requires a sales conversation, unlike consumer AI writing tools.
  • Its proprietary Palmyra models are less widely benchmarked and documented than general-purpose models like GPT or Claude.
  • Primarily positioned for large enterprises, making it less accessible or cost-effective for individuals and small teams.

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

Writer

On request
  • Starter$undefined/month
    • For teams starting with agentic AI
    • Up to 5 users
    • 14-day free trial, no card required
  • Enterprise$undefined/month
    • Contact sales
    • Unlimited users, teams and free collaborators
    • Lite seats for invited users

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 Writer if

  • You need palmyra llms.
  • You work on web, api.
  • You also want knowledge graph.
Writer review

Questions people ask

Is Arize AI or Writer better?
Neither clearly leads. Arize AI starts at Free and Writer at On request, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Arize AI or Writer?
Arize AI has a free tier; the other does not. Paid plans start at Free for Arize AI and On request for Writer.
Does Arize AI or Writer run on more platforms?
Both run on web, api, so platform support will not decide this one for you.
Can I use Arize AI for free?
Yes. Arize AI has a free tier, so you can try it without paying. Writer starts at On request.
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 Writer is typically brought in for.
What can Arize AI do that Writer cannot?
Arize AI covers End-to-end tracing, Evaluation framework, Prompt testing and improvement, Alyx AI engineering agent. Writer covers Palmyra LLMs, Knowledge Graph, No-code agent builder, Brand compliance.

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
Writer: What does Writer cost?

Writer does not publish prices. There are two tiers: Starter, for teams up to five users, with a 14-day free trial and no card required, and Enterprise, which is contact-sales and adds unlimited users and teams.

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
Writer: What is the difference between Pro and Lite seats?

Pro is the standard paid seat, with full access to create, customise and automate workflows. Lite seats exist only on Enterprise, letting invited users view and run existing playbooks with limited monthly Agent use before needing a Pro seat.

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
Writer: What does Writer do with customer data?

Writer states a zero data retention approach and says customers retain full ownership of their data. By default it does not train or improve its models on customer data, rather than requiring an opt-out.

Source
Writer: Which compliance standards does Writer meet?

Writer says it adheres to GDPR, HIPAA, SOC 2 Type II and PCI. HIPAA and SOC 2 Type II certifications and reports are available on request, and only for Enterprise plans.

Source
Writer: Are there discounts for nonprofits or education?

Yes. Writer offers 20% off the Starter and Enterprise plans to nonprofits and educational institutions, claimed by emailing from a nonprofit or .edu address.

Source
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