Claude Opus 5.5 for Chemical Companies: First Place, and What It Costs

What Claude Opus 5.5 is.

Anthropic released Claude Opus 5.5 on 22 September 2026. It reads text and images, holds up to 1 million tokens, and costs $4 for every million tokens you send and $20 for every million it writes. Anthropic says it “performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5.”

You choose how hard it thinks, from low to max. Each test on this page names the setting it ran.

Twice the token price is not twice the bill.

Opus 5.5's tokens cost twice what Sonnet 5.5's do. Three tests ran both models on the same work and published what it cost. The dashed line is what the token price predicts; the bar is what each test measured.

Where Opus 5.5 leads.

Three of the guide's jobs have a test that ran it.

Opus 5.5 compared with Sonnet 5.5 and Fable 5.1.

Anthropic's three largest models, on the tests that ran all three.

Where Opus 5.5 is not the pick.

First place is not always worth its price. These are the places the tests say so.

• Regulatory Research Costs Most Here

  It scores 65.15%, inside the leader's margin, at $22.21 a question: the dearest of the 23 results in the leading group. Sonnet 5.5 scored higher for $12.64.

  vals.ai Legal Research, regulatory questions6 Oct 2026

• Cheaper Readers Come Close on Tables

  At its high setting it leads the table test at 6.13 cents a page. A Gemini 3 Flash setting is 4.4 points behind at 0.65 cents. A free 1.2B model leads the independent document test.

  ParseBench leaderboard29 Sep 2026

• Parsing Services Lead Whole Documents

  On whole documents it is 6th of 142, behind five document parsing services. Three of them are sold by the test's maker, so check a second test before you choose.

  ParseBench leaderboard29 Sep 2026

• Long Answers Raise the Bill

  At its max setting it wrote about 119,000 tokens per index task, against about 73,000 for Opus 5. Every one of them is charged at $20 a million.

  Artificial Analysis: Claude Opus 5.5 takes the top spot on the Intelligence Index22 Sep 2026

How to test Opus 5.5 against a cheaper model.

The tests disagree on what Opus costs you, so measure it on your own work.

1. 1

   Pick One Real Job

   Choose one job you run often: a price list to pull, a customer report, or a regulatory question.

   You end withOne job, with work your team has already checked

2. 2

   Run It on Both

   Run 20 real examples through Opus 5.5 and through a cheaper model, at the same setting.

   You end with40 answers, side by side

3. 3

   Count the Bill, Not the Price

   Add up what each run cost from your account's usage, not from the price list.

   You end withWhat each model really costs on your work

4. 4

   Check Every Answer

   Mark each answer right or wrong against the work your team checked.

   You end withYour own score for each model

5. 5

   Pay for the Gap Where It Shows

   Use Opus where its score is clearly higher, and the cheaper model where the two are level.

   You end withA model for each job, chosen on your evidence

Questions about Claude Opus 5.5.

Short answers, from the same sources as the rest of this page.