Claude Sonnet 4.5
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...
Updated 37 min ago · first seen 11 Sept 2026
model_01M293VBDY6MGVRK53W1PBAGB3
- Context
- 1M tokens
- T2 · 4 h ago
- Released
- 29 Sept 2025
- T2 · 4 h ago
- Knowledge cutoff
- Jan 2025
- T2 · 4 h ago
Specification
- Family
- Claude
Source:Claude Developer Platform docsT1observed 4 h agohigh
- Release date
- 29 Sept 2025
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Status
- active
Source:Claude Developer Platform docsT1observed 4 h agohigh
- Openness
- proprietary
Source:Claude Developer Platform docsT1observed 4 h agohigh
- Context window
- 1M tokens
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Max output
- 64K tokens
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Knowledge cutoff
- Jan 2025
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Modalities
- image, text
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Input modalities
- image, text
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Output modalities
- text
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Tokenizer
- Claude
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Retirement date
- 29 Sept 2026
Source:Claude Developer Platform docsT1observed 4 h agohigh
- Retirement tentative
- Yes
Source:Claude Developer Platform docsT1observed 4 h agohigh
- File input
- Yes
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Aa median output tokens per second
- 38
Source:Artificial AnalysisT2observed 2 h agomedium
- Openrouter id
- anthropic/claude-sonnet-4.5
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Supported parameters
- include_reasoning, max_completion_tokens, max_tokens, reasoning, response_format, stop, structured_outputs, temperature, tool_choice, tools, top_k, top_p
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
Each value shows its source, tier and observation time. Conflicting claims are kept side by side and flagged — never averaged. How AI Atlas records facts →
Provenance
Attributed facts
22
Source tiers
T1T25 / 17
Freshest observation
37 min ago
Conflicts
1 flagged
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
- 1M tokens
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Max output
- 64K tokens
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Knowledge cutoff
- Jan 2025
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Tokenizer
- Claude
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
| Benchmark | Score | Metric | Config | Evaluated | Source |
|---|---|---|---|---|---|
| τ²-bench | 70.47% | pass^1 | aa_slug=claude-4-5-sonnet · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Artificial Analysis Intelligence Index | 19.34 | index | aa_slug=claude-4-5-sonnet · version=4.3 · estimated=true | — | artificialanalysis.aiT2 |
| GPQA | 72.73% | accuracy | aa_slug=claude-4-5-sonnet · variant=GPQA Diamond · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Humanity's Last Exam | 7.23% | accuracy | aa_slug=claude-4-5-sonnet · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| IFBench | 42.65% | accuracy | aa_slug=claude-4-5-sonnet · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| MMMU-Pro | 65.2% | accuracy | aa_slug=claude-4-5-sonnet · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Terminal-Bench | 28.79% | accuracy | aa_slug=claude-4-5-sonnet · variant=hard · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
Scores are reported as published, with their evaluation configuration (harness, prompting, judge). Results with different configs are not directly comparable — see methodology.
Current prices
| 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 | 37 min ago | openrouter.aiT2 |
| Anthropic API | $3 | $15 | $0.30 | — | — | 4 h ago | platform.claude.comT1 |
| Anthropic APIanthropic/claude-sonnet-4.5 | $3 | $15 | $0.30 | — | 1M | 37 min 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.
Available through 1
Price history
Input price · USD / 1M tokens
Output price · USD / 1M tokens
- Anthropic API
No hardware estimate available
No lineage recorded
Papers 0
No papers linked yet.
Repositories 0
No repositories linked yet.
As of
Rewind the record: see this entity's attributes exactly as AI Atlas knew them on a given day.
Claim history · Reasoning
Reasoningreasoning3
| Value | Valid from → to | Status | Source | Confidence | Extractor |
|---|---|---|---|---|---|
| Yes | → current | current | OpenRouter public model & pricing listingT2 | medium | deterministic |
| No | → | superseded | Artificial AnalysisT2 | medium | deterministic |
| Yes | → | superseded | 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 →
Claude Sonnet 4.5: reasoning changed from false to true
ReasoningNo→YesopenrouterClaude Sonnet 4.5 scores 28.79% on Terminal-Bench
artificial_analysisClaude Sonnet 4.5 scores 70.47% on τ²-bench
artificial_analysisClaude Sonnet 4.5 scores 65.2% on MMMU-Pro
artificial_analysisClaude Sonnet 4.5 scores 42.65% on IFBench
artificial_analysisClaude Sonnet 4.5 scores 7.23% on Humanity's Last Exam
artificial_analysisClaude Sonnet 4.5 scores 72.73% on GPQA
artificial_analysisClaude Sonnet 4.5 scores 19.34 on Artificial Analysis Intelligence Index
artificial_analysisClaude Sonnet 4.5: reasoning changed from true to false
ReasoningYes→Noartificial_analysisAnthropic API lists Claude Sonnet 4.5 at $1.5 in / $7.5 out per 1M tokens
openrouterAnthropic API lists Claude Sonnet 4.5 at $3 in / $15 out per 1M tokens
openrouterAnthropic API lists Claude Sonnet 4.5 at $3 in / $15 out per 1M tokens
anthropic
| 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 | 19 min ago | 1 |
| Claude Developer Platform docs | docs.claude.com/en/docs/about-claude/pricing.md | pricing | T1· Official | 19 min ago | 1 |
| OpenRouter public model & pricing listing | openrouter.ai/api/v1/models | catalogue | T2· Quality secondary | 37 min ago | 3 |
| Artificial Analysis | artificialanalysis.ai/leaderboards/models | leaderboard | T2· Quality secondary | 2 h ago | 1 |
Tier 1 = official/primary, 2 = quality secondary, 3 = community, 4 = unverified. Every snapshot is archived; see all sources and the methodology.