Overview

Identity

Identity block not returned by the API for this entity.

Openness

Openness not classified yet — no sourced evidence to place this model in the ontology.

Key facts

Release date: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium
Status: Source:Claude Developer Platform docsT1observed 13 h agohigh
Knowledge cutoff: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium
Retirement date: Source:Claude Developer Platform docsT1observed 13 h agohigh
Openrouter id: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium

Architecture

Tokenizer: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium

Capabilities

Modalities

Modalities: imagetext
Input: imagetext
Output: text

Capabilities

Tool calling
Yes
OpenRouter public model & pricing listing · T2
Structured output
Yes
OpenRouter public model & pricing listing · T2
Reasoning
Yes
OpenRouter public model & pricing listing · T2
Vision
Yes
OpenRouter public model & pricing listing · T2
Audio
Unavailable
Fine-tuning available
Unavailable

Context window: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium
Max output: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium
Knowledge cutoff: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium
Tokenizer: Source:OpenRouter public model & pricing listingT2observed 13 h agomedium

Benchmarks7

Compare with another model →

Comparable same task and conditions · Partially comparable same task, conditions differ (effort, temperature, judge) · Not comparable different variant or metric

No benchmark results recorded

Results appear when a tier 1–3 source publishes them; we never copy scores without a source.

Providers & Pricing3

All offers in the price terminal →

Current prices per 1M tokens
Provider	Input / 1M	Output / 1M	Cached in	Batch in / out	Context	Observed	Source
Anthropic APIanthropic/claude-sonnet-4.5:batch	$1.5	$7.5	$0.15	—	1M	6 h ago	openrouter.aiT2
Anthropic API	$3	$15	$0.30	—	—	13 h ago	platform.claude.comT1
Anthropic APIanthropic/claude-sonnet-4.5	$3	$15	$0.30	—	1M	6 h ago	openrouter.aiT2

USD per 1M tokens as published by each provider (USD). Rows are append-only: every change is kept in the history below.

Price history

Step lines per provider; amber markers are recorded changes. Click a marker or a row for the evidence behind that price.

Output price · USD / 1M tokens 1 provider

Anthropic API

Anthropic API$15 → $7.511 Sept 2026
Anthropic APIfirst observed $1511 Sept 2026

Input price · USD / 1M tokens 1 provider

Anthropic API

Anthropic API$3 → $1.511 Sept 2026
Anthropic APIfirst observed $311 Sept 2026

Timeline13

Full timeline →

12 Sept 2026
Property changedModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5: reasoning changed from false to true
ReasoningNo→Yesopenrouter
openrouter.ai
11 Sept 2026
Benchmark resultModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5 scores 28.79% on Terminal-Bench
artificial_analysis
artificialanalysis.ai
11 Sept 2026
Benchmark resultModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5 scores 70.47% on τ²-bench
artificial_analysis
artificialanalysis.ai
11 Sept 2026
Benchmark resultModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5 scores 65.2% on MMMU-Pro
artificial_analysis
artificialanalysis.ai
11 Sept 2026
Benchmark resultModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5 scores 42.65% on IFBench
artificial_analysis
artificialanalysis.ai
11 Sept 2026
Benchmark resultModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5 scores 7.23% on Humanity's Last Exam
artificial_analysis
artificialanalysis.ai
11 Sept 2026
Benchmark resultModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5 scores 72.73% on GPQA
artificial_analysis
artificialanalysis.ai
11 Sept 2026
Benchmark resultModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5 scores 19.34 on Artificial Analysis Intelligence Index
artificial_analysis
artificialanalysis.ai
11 Sept 2026
Property changedModelClaude Sonnet 4.5Anthropic
Claude Sonnet 4.5: reasoning changed from true to false
ReasoningYes→Noartificial_analysis
artificialanalysis.ai
11 Sept 2026
Listed by providerModelClaude Sonnet 4.5Anthropic
Anthropic API lists Claude Sonnet 4.5 at $1.5 in / $7.5 out per 1M tokens
openrouter
openrouter.ai
11 Sept 2026
Listed by providerModelClaude Sonnet 4.5Anthropic
Anthropic API lists Claude Sonnet 4.5 at $3 in / $15 out per 1M tokens
openrouter
openrouter.ai
11 Sept 2026
New modelModelClaude Sonnet 4.5Anthropic
New model: Claude Sonnet 4.5 (Anthropic)
anthropic
platform.claude.com
11 Sept 2026
Listed by providerModelClaude Sonnet 4.5Anthropic
Anthropic API lists Claude Sonnet 4.5 at $3 in / $15 out per 1M tokens
anthropic
platform.claude.com

Change history25

Temporal, append-only claims: a new observation closes the previous claim instead of overwriting it. Rewind the record with the as-of picker.

Viewing AI Atlas as of 12 Mar 2026 — attributes exactly as the atlas knew them on that day; later corrections are not shown.

Back to today →

Claude Sonnet 4.5 was not yet in AI Atlas on 12 Mar 2026

First seen 11 Sept 2026. Nothing is inferred backwards: no attribute is shown for dates before the first observation.

25 claims · 22 properties1 conflicting

Familyfamily1

Claim history for Family
Value	Valid from → to	Status	Source	Confidence	Extractor
Claude	11 Sept 2026 20:51 UTC → current	current	Claude Developer Platform docsT1	high	deterministic

Release daterelease_date1

Claim history for Release date
Value	Valid from → to	Status	Source	Confidence	Extractor
29 Sept 2025	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Statusstatus2conflicting claims

Claim history for Status
Value	Valid from → to	Status	Source	Confidence	Extractor
deprecated	11 Sept 2026 22:42 UTC → current	conflicting	Artificial AnalysisT2	medium	deterministic
active	11 Sept 2026 20:51 UTC → current	current	Claude Developer Platform docsT1	conflicted	deterministic

Opennessopenness1

Claim history for Openness
Value	Valid from → to	Status	Source	Confidence	Extractor
proprietary	11 Sept 2026 20:51 UTC → current	current	Claude Developer Platform docsT1	high	deterministic

Context windowcontext_length1

Claim history for Context window
Value	Valid from → to	Status	Source	Confidence	Extractor
1M tokens	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Max outputmax_output_tokens1

Claim history for Max output
Value	Valid from → to	Status	Source	Confidence	Extractor
64K tokens	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Knowledge cutoffknowledge_cutoff1

Claim history for Knowledge cutoff
Value	Valid from → to	Status	Source	Confidence	Extractor
Jan 2025	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Modalitiesmodalities1

Claim history for Modalities
Value	Valid from → to	Status	Source	Confidence	Extractor
image, text	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Input modalitiesmodalities_input1

Claim history for Input modalities
Value	Valid from → to	Status	Source	Confidence	Extractor
image, text	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Output modalitiesmodalities_output1

Claim history for Output modalities
Value	Valid from → to	Status	Source	Confidence	Extractor
text	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Tokenizertokenizer1

Claim history for Tokenizer
Value	Valid from → to	Status	Source	Confidence	Extractor
Claude	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Retirement dateretirement_date1

Claim history for Retirement date
Value	Valid from → to	Status	Source	Confidence	Extractor
29 Sept 2026	11 Sept 2026 20:51 UTC → current	current	Claude Developer Platform docsT1	high	deterministic

Retirement tentativeretirement_tentative1

Claim history for Retirement tentative
Value	Valid from → to	Status	Source	Confidence	Extractor
Yes	11 Sept 2026 20:51 UTC → current	current	Claude Developer Platform docsT1	high	deterministic

Descriptiondescription1

Claim history for Description
Value	Valid from → to	Status	Source	Confidence	Extractor
Claude Sonnet 4.5 is Anthropic’s most advanced Sonnet model to date, optimized for real-world agents and coding workflows. It delivers state-of-the-art performance on coding benchmarks such as SWE-bench Verified, with...	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

File inputfile_input1

Claim history for File input
Value	Valid from → to	Status	Source	Confidence	Extractor
Yes	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Aa median output tokens per secondmetric.aa_median_output_tokens_per_second1

Claim history for Aa median output tokens per second
Value	Valid from → to	Status	Source	Confidence	Extractor
38	11 Sept 2026 22:42 UTC → current	current	Artificial AnalysisT2	medium	deterministic

Openrouter idopenrouter_id1

Claim history for Openrouter id
Value	Valid from → to	Status	Source	Confidence	Extractor
anthropic/claude-sonnet-4.5	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Reasoningreasoning3

Claim history for Reasoning
Value	Valid from → to	Status	Source	Confidence	Extractor
Yes	12 Sept 2026 00:05 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic
No	11 Sept 2026 22:42 UTC → 12 Sept 2026 00:05 UTC	superseded	Artificial AnalysisT2	medium	deterministic
Yes	11 Sept 2026 21:10 UTC → 11 Sept 2026 22:42 UTC	superseded	OpenRouter public model & pricing listingT2	medium	deterministic

Structured outputstructured_output1

Claim history for Structured output
Value	Valid from → to	Status	Source	Confidence	Extractor
Yes	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Supported parameterssupported_parameters1

Claim history for Supported parameters
Value	Valid from → to	Status	Source	Confidence	Extractor
include_reasoning, max_completion_tokens, max_tokens, reasoning, response_format, stop, structured_outputs, temperature, tool_choice, tools, top_k, top_p	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Tool callingtool_calling1

Claim history for Tool calling
Value	Valid from → to	Status	Source	Confidence	Extractor
Yes	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Visionvision1

Claim history for Vision
Value	Valid from → to	Status	Source	Confidence	Extractor
Yes	11 Sept 2026 21:10 UTC → current	current	OpenRouter public model & pricing listingT2	medium	deterministic

Claims are temporal and append-only: a new observation closes the previous claim (valid_to) instead of overwriting it. Conflicting claims from different sources are kept side by side and flagged — never averaged. Methodology →

Provenance

Attributed facts

23

Source tiers

T1T25 / 18

Freshest observation

6 h ago

Conflicts

1 flagged

Source documents 4

Source documents
Source	Document	Type	Tier	Last observed	Snapshots
Claude Developer Platform docs	docs.claude.com/en/docs/about-claude/model-deprecations.md	model_docs	T1· Official	7 h ago	1
Claude Developer Platform docs	docs.claude.com/en/docs/about-claude/pricing.md	pricing	T1· Official	7 h ago	1
OpenRouter public model & pricing listing	openrouter.ai/api/v1/models	catalogue	T2· Quality secondary	6 h ago	5
Artificial Analysis	artificialanalysis.ai/leaderboards/models	leaderboard	T2· Quality secondary	11 h ago	1

Tier 1 = official/primary, 2 = quality secondary, 3 = community, 4 = unverified. Every snapshot is archived; see all sources and the methodology.

Data quality (65/100) measures how well AI Atlas knows this entity — completeness, primary-source ratio, freshness, conflicts — never how good the model is. Methodology →