Arbitr vs Acrolinx
Acrolinx, now Markup AI, checks content for style, tone, terminology and clarity. Arbitr checks content against what you’ve approved for each market: claims, prices, specifications and rules. Here’s how they compare, and when you’d choose each.
Chris Connell, Arbitr
Published October 29, 2026. Last reviewed October 29, 2026.
What’s the difference between Arbitr and Acrolinx?
Acrolinx is now Markup AI, a content checking platform. Its Content Guardian Agents scan, score and rewrite content against a company’s standards for terminology, consistency, tone, clarity, and spelling and grammar, whether people or AI wrote it. It builds on the configurable rules engine Acrolinx developed over 20 years.
Arbitr is an AI context platform for content. Its governed memory, Cortex, holds what a company has approved (claims, prices, terms and rules), each with an owner, the markets and languages it applies to, its evidence and the period it’s in force. Arbitr’s agents create and check content against that memory, before and after it’s published.
Choose Acrolinx If your only priority is consistent style, tone and terminology.
Choose Arbitr If your only priority is making sure claims, prices, specifications and rules are right for every market and language.
Choose both If you use Acrolinx for how you write and need what you say checked against what you’ve approved.
Arbitr vs Acrolinx: features, pricing and languages
Our own comparison, based on publicly available information. Last checked October 29, 2026.
| Feature |  | Acrolinx |
|---|---|---|
| What it is | AI context platform for content: a governed memory of what’s approved (Cortex) plus agents that create and check content against it | Content checking platform with Content Guardian Agents, formerly Acrolinx |
| Main job | Keep content right for every market: create from what’s approved and check content before and after it goes out | Scan, score and rewrite content to meet standards for terminology, consistency, tone, clarity, and spelling and grammar |
| Built for | Teams who own what gets said: marketing, product content, localization and legal | Technical writers and content teams, with a long history in healthcare, finance, manufacturing and high tech |
| Where its knowledge lives | Cortex. Every entry has an owner, a scope (market, language, channel, audience), its evidence and the dates it’s in force. Approved decisions govern; drafts and past content don’t | Style guides, terminology lists and the configurable rules engine carried over from Acrolinx |
| Whose content it checks | Content from any source: your people, agencies, partners and any AI tool, through Word, Google Docs, API and MCP | Content from people and AI, through API and MCP, and tools such as Cursor, Figma, ChatGPT, GitHub Actions, Zapier and Contentful |
| Content already published | Scans what you’ve already published and flags what no longer matches what’s approved, including after a decision changes | Automated content audits, according to Markup AI’s launch announcement |
| Markets and regions | Market and language are held separately, so content can be right for Germany and right for Austria, even in the same language | Not presented on Markup AI’s website as of October 29, 2026 |
| Languages | Creates and checks content in 120+ languages | Language coverage not presented on its website; software directory listings show English |
| When a person is needed | You set the bar. What falls below it goes to your nominated reviewer, or to an accredited expert from Arbitr’s network of 37,000 working to your rules | Scores content and suggests or applies rewrites against the standards a team sets |
| Record of what happened | Every check records what was checked, the approved entry it was checked against, what was held, who decided and when | Content quality scores against your standards |
| Models | Small custom models, run on IBM watsonx; knowledge stays in Cortex, not in the model | AI agents combined with the deterministic rules engine from Acrolinx |
| Pricing | See Arbitr pricing | Usage based, packaged by tokens; free trial available |
| Security | SOC 2 in progress. IBM Platinum Partner | Not presented in the sources we reviewed |
Where Acrolinx is strong, and where Arbitr leads
Acrolinx checks how you write. Arbitr checks what you say.
Where Acrolinx is strong
- Deep heritage. More than 20 years of content governance and terminology work, especially in technical documentation.
- Configurable rules. A deterministic rules engine for terminology, clarity and consistency, now paired with AI agents.
- Built for developers. API- and MCP-first, so checks can run in pipelines, authoring tools and AI assistants.
- Easy to start. A free trial and usage-based pricing make it simple to try.
Where Arbitr leads
- It checks what you’ve approved, not just how you write. Claims, prices, specifications and policies are checked against the decision that governs them, and who made it.
- Right for each market. Market and language are held separately, so content is checked against the rules for where it’s going.
- It keeps live content right. When a price, claim or policy changes, Arbitr finds where the old version is still published, including translations and paraphrases.
- Experts when you need them. What falls below your bar goes to your reviewer, or to an accredited expert from a network of 37,000.
Why “right” matters more than “consistent”
Consistency sounds like the goal until you sell in more than one market. The same product page often needs to say different things in different places, and every version needs to be right.
41 miles per gallon
Right for US5.7 L/100 km
Right for AU5,7 l/100 km
Right for DEArbitr or Acrolinx: which should you choose?
Acrolinx may suit you if
- Your main need is consistent style, tone, terminology and clarity
- You want checks wired into developer pipelines and authoring tools
- You want to start self-serve, with usage-based pricing
Arbitr may suit you if
- You publish across markets and languages, and each has its own claims, prices and rules
- A wrong claim, price or specification costs you more than a wrong comma
- You need to know what’s already live is still right when a decision changes
Use both if
- You use Acrolinx for how your teams write, and want Arbitr to check what they say against what you’ve approved
Arbitr vs Acrolinx: FAQs
What is the main difference between Arbitr and Acrolinx?
Acrolinx, now Markup AI, checks how content is written: terminology, consistency, tone, clarity, and spelling and grammar. Arbitr checks what content says against what a company has approved for each market, such as claims, prices, specifications and rules, and creates content from that approved record.
Is Acrolinx now Markup AI?
Yes. Acrolinx became Markup AI, which describes itself as a content checking platform built on Acrolinx’s rules engine, with AI agents added.
Can Arbitr and Acrolinx be used together?
Yes. Teams can use Acrolinx for style and terminology, and Arbitr to check that claims, prices, specifications and rules are right for each market before and after content is published.
Does Acrolinx check claims?
Markup AI says its newer agents help identify unfounded claims. Arbitr checks each claim against the specific approved entry that governs it, with its owner, the markets it applies to and the dates it’s in force.
How is Acrolinx priced compared with Arbitr?
Markup AI prices by usage, packaged by tokens, with a free trial. Arbitr doesn’t price per seat; pricing is set with each customer.
Is Arbitr an alternative to Acrolinx?
For style and terminology checking alone, Arbitr isn’t a like-for-like replacement. If your goal is making sure what you publish is right for every market, Arbitr covers work Acrolinx doesn’t present today, such as checking content against approved claims and rules per market.
Sources
- Markup AI, “Acrolinx has become Markup AI.” markup.ai.
- Markup AI, funding and Content Guardian Agents announcement, September 17, 2025. Business Wire.
- The Gilbane Advisor, coverage of the Markup AI launch, September 2025. gilbane.com.
- Capterra, Markup AI listing (pricing model, languages), 2026. capterra.com.
About this comparison
How we compared. We used Markup AI’s public website, documentation and announcements, and our own product documentation to compile this comparison. Where Markup AI’s site doesn’t describe a capability, we say “not presented.” Information on this page may be incomplete or change. Do your own research.
Who wrote this. Arbitr wrote this page, so we’re not neutral. We’ve aimed to describe Acrolinx fairly, and we’ll correct anything that’s wrong. Email marketing@arbitr.ai.