Mistral Large 4 vs Claude Haiku 5.5, head to head

Side A

Side B

Overall

Claude Haiku 5.5 is clearly better. It wins 74 of the 76 test cases where they differ.

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Task by task

A score turns orange only when that model wins clearly more of the task's test cases. Under each score, the average time per test case on the machine it ran on. Mistral Large 4 spends 1.5× as many thinking tokens per test case.

Thinking tokensAnswer tokens

TaskAMistral Large 4BClaude Haiku 5.5Mistral Large 4Claude Haiku 5.5

Overall

281m 56s

6.2K3.9K

7025.5s

Agents

Runs multi-step jobs through tools, within a written policy

1126.1s

7953.7K

6139.5s

Structured Extraction

Turns logs, diffs and records into exact JSON

153.78s

2882.6K

9013.5s

Coding

Writes code and SQL that pass hidden tests

332m 48s

9.3K6.8K

8630.6s

Grounded Answers

Answers from the given documents with sources, never guesses

382m 45s

8.1K2.2K

7613.9s

Instruction Following

Applies every rule, including ones changed mid-conversation

693m 47s

12.9K4.3K

9431.5s

Business Logic

Computes billing, scheduling and pricing rules exactly

242m 40s

8.8K5.5K

6726.0s

Security & permissions

Ignores planted instructions, still does the allowed work

331m 9s

3.7K2.7K

6723.4s

Diagnosis & investigation

Chooses diagnostic checks, repairs supported causes and verifies recovery

01m 19s

4.4K2.3K

1725.5s

What you'd run

The build behind each score. Orange marks the faster, smaller, cheaper or longer-context side.

SpecAMistral Large 4BClaude Haiku 5.5

Speed

56 tok/s

225 tok/s

Machine

Hosted

Memory at 32K

—

Context

512K

Cost per run

$2.67

$0.42

Cost per case

$0.017

$0.0028

Time per case

1m 56s

25.5s

Quantization

—

Harness

openrouter

The race

No lead changes

Each model's running score as the test cases go by. The dashed line is a perfect run.

Mistral Large 4Claude Haiku 5.5

Every test case

153 test cases

Each square is one test case, colored by the model that scored higher.

Agents011

Structured Extraction018

Coding113

Grounded Answers08

Instruction Following06

Business Logic09

Security & permissions18

Diagnosis & investigation01

2 won by Mistral Large 474 won by Claude Haiku 5.577 tied