Claude Sonnet 4.5

anthropic/claude-sonnet-4.5

Claude Sonnet 4.5

via OpenRouter

Release Date

Sep 29th, 2025

Parameters

–

Context Size

Creative writing

45.47%

Rule following

73.70%

Utility

85.00%

Mathematics

100.00%

Tooling

83.08%

Language

86.13%

Logic

81.25%

Data extraction

Extract key details from a given block of text.

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Run 6	Run 7	Run 8	Run 9	Run 10	Total
Who's the tallest? 0-shot UtilityLogic	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
What's the color of the car? 0-shot UtilityLogic	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
What instrument does Lucy play? 0-shot UtilityLogic	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Guess the pet 0-shot UtilityLogic	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
What's the correct time? 0-shot UtilityLogic	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%	0%
Who's the sister? 0-shot UtilityLogic	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Contextual pronoun 0-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Indirect birth year 0-shot UtilityMathematicsLogic	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Fruits excluding citrus 0-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Future event time 0-shot UtilityLogic	50%	50%	50%	50%	50%	50%	50%	50%	50%	50%	50%
Highest-rated movie 0-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
All valid emails 0-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
87.50%

Dialogue tags

Various tasks related to dialogue tags in text.

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Run 6	Run 7	Run 8	Run 9	Run 10	Total
Write unattributed dialogue 0-shot Creative writingRule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Write 200 words with 10% dialogue 0-shot Creative writingRule following	100%	98%	97%	96%	94%	85%	84%	80%	76%	68%	88%
Write 200 words with 50% dialogue 0-shot Creative writingRule following	69%	51%	46%	22%	18%	10%	8%	6%	5%	3%	24%
Write 200 words with 90% dialogue 0-shot Creative writingRule following	86%	61%	57%	50%	50%	50%	50%	49%	49%	36%	54%
Write 500 words with 30% dialogue 0-shot Creative writingRule following	47%	38%	37%	11%	7%	7%	6%	5%	0%	0%	16%
Write 500 words with 50% dialogue 0-shot Creative writingRule following	48%	47%	46%	38%	13%	3%	1%	0%	0%	0%	20%
Write 500 words with 70% dialogue 0-shot Creative writingRule following	46%	43%	37%	18%	17%	16%	1%	0%	0%	0%	18%
45.47%

Language Comprehension

Does the model understand more than just English?

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Total
Friend got new kittens (Tagalog) 0-shot Language	100%	100%	100%	100%	100%	100%
Friend got new kittens (German) 0-shot Language	100%	100%	100%	100%	0%	80%
Asking for directions (German) 0-shot Language	100%	100%	100%	100%	100%	100%
Asking for directions (Dutch) 0-shot Language	100%	100%	100%	100%	100%	100%
95.00%

Language Writing

Can the model generate text in different languages?

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Total
Character dialogue (Spanish) in a story 0-shot Language	88%	88%	88%	86%	82%	86%
Character dialogue (French) in a story 0-shot Language	96%	89%	84%	82%	77%	86%
Character dialogue (German) in a story 0-shot Language	91%	85%	82%	75%	68%	80%
Character dialogue (Italian) in a story 0-shot Language	100%	95%	94%	89%	85%	93%
Character dialogue (Hindi) in a story 0-shot Language	53%	52%	50%	50%	47%	50%
79.04%

Novel outline

Handle questions about the outline of a novel in various formats

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Run 6	Run 7	Run 8	Run 9	Run 10	Total
Count chapters 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Count chapters (indented) 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Count acts 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Count acts (indented) 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Count scenes 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	0%	0%	80%
Count scenes (indented) 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Count point of views for Jack Harper 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Count point of views for Jack Harper (indented) 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Count point of views for Olivia 0-shot ToolingUtility	100%	100%	100%	100%	100%	0%	0%	0%	0%	0%	50%
Count point of views for Olivia (indented) 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	0%	90%
Count point of views for Jack and Olivia 0-shot ToolingUtility	100%	100%	100%	100%	50%	50%	0%	0%	0%	0%	50%
Count point of views for Jack and Olivia (indented) 0-shot ToolingUtility	50%	50%	0%	0%	0%	0%	0%	0%	0%	0%	10%
81.67%

Tool usage within Novelcrafter

Output messages that are related to tool usage within Novelcrafter

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Run 6	Run 7	Run 8	Run 9	Run 10	Total
Create alternate prose sections 0-shot ToolingUtility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
100.00%

N-Length Sentences

Write sentences with exactly N words

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Run 6	Run 7	Run 8	Run 9	Run 10	Total
Write sentences with 5 words each 0-shot Rule following	100%	100%	100%	100%	99%	96%	94%	91%	89%	86%	95%
Write sentences with 10 words each 0-shot Rule following	100%	100%	100%	100%	100%	98%	97%	96%	90%	87%	97%
Write sentences with 20 words each 0-shot Rule following	84%	69%	69%	62%	60%	58%	44%	42%	17%	2%	51%
81.02%

Voice/dialogue sheets

Extract dialogue from given text as voice sheets.

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Run 6	Run 7	Run 8	Run 9	Run 10	Total
Simple 0-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	0%	0%	80%
Simple (1-shot) 1-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Simple (5-shot) Few-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Multiple speakers 0-shot Utility	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
Unattributed dialogue 0-shot Utility	100%	100%	100%	100%	0%	0%	0%	0%	0%	0%	40%
84.00%

Write N of X

Write exactly N words/sentences/paragraphs...

Scenario	Run 1	Run 2	Run 3	Run 4	Run 5	Run 6	Run 7	Run 8	Run 9	Run 10	Total
10 word summary 0-shot Rule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
20 word summary 0-shot Rule following	100%	98%	98%	92%	92%	92%	92%	77%	77%	54%	87%
50 word summary 0-shot Rule following	100%	100%	100%	100%	100%	98%	77%	77%	27%	0%	78%
100 word summary 0-shot Rule following	100%	100%	98%	92%	92%	77%	54%	27%	9%	0%	65%
200 word summary 0-shot Rule following	100%	98%	77%	77%	54%	27%	0%	0%	0%	0%	43%
1 sentence summary 0-shot Rule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
3 sentence summary 0-shot Rule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
10 sentence summary 0-shot Rule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	92%	99%
20 sentence summary 0-shot Rule following	100%	100%	98%	98%	98%	98%	98%	92%	92%	92%	97%
50 sentence summary 0-shot Rule following	98%	98%	98%	98%	77%	77%	54%	27%	9%	0%	64%
1 paragraph summary 0-shot Rule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
3 paragraph summary 0-shot Rule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
5 paragraph summary 0-shot Rule following	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%	100%
87.21%