Language

Claude 2.1

By Anthropic, in the Claude family.

Released
21 Nov 2023
Status
Retired
Retired
21 Jul 2025
Context
200K
Max output
4.1K
Input per 1M tokens
$8.00
Output per 1M tokens
$24.00
Open weights
No
License
proprietary
Parameters
—
Knowledge cutoff
—
Reasoning
No
Modalities
text → text

Category scores

Out of 100, from independent and third-party results only, by method category-2026-09-29.1.

Not enough independent results yet

Only independent and third-party results rank a model; self-reported and unattributed numbers never do.

Benchmark results

Every result we hold for this model, with who ran it and where it was published.

Knowledge & reasoning

Knowledge & reasoning results
BenchmarkMetricValueProvenanceSettingEvaluatedSource
DTBench (Decision Theory Benchmark)Accuracy (capability questions)51.0%Third party——https://conceptualreasoning.ai/dtbench via Epoch AI
MMLUAccuracy73.5%Third party——Stanford CRFM Leaderboard via Epoch AI

Scientific reasoning

Scientific reasoning results
BenchmarkMetricValueProvenanceSettingEvaluatedSource
GPQA DiamondAccuracy33.0%Independent—27 Jan 2025Epoch AI

Mathematics

Mathematics results
BenchmarkMetricValueProvenanceSettingEvaluatedSource
OTIS Mock AIME 2024-2025Accuracy1.9%Independent—7 Mar 2025Epoch AI

Coding & software engineering

Coding & software engineering results
BenchmarkMetricValueProvenanceSettingEvaluatedSource
WeirdML (v2)Average accuracy7.1%Third party——https://htihle.github.io/weirdml.html via Epoch AI

Other Claude versions

Sources