Private AI

Nano GPT logo
NanoGPT
Nano GPT logo
NanoGPT
Nano GPT logo
NanoGPT
Search
 
 
 
 
All conversations

Create

Chat
Studio

Explore

Models
Pricing
AI Apps
Blog

Library

Gallery
Workspace
Usage & billing
API
Suggestions and bugs
Use cases

|

Terms

|

Privacy

|

Refunds
Usage & billing
Teams
Referrals
Presets
Settings
FAQPress & mediaBrand assetsBenchmarksNano RPCEarn crypto
  1. Models
  2. Text
  3. Anthropic

Claude Sonnet 4.5 Thinking

Adds extended, step‑by‑step reasoning for tougher coding, planning, and multi‑tool tasks. Ideal for long‑horizon agent workflows, complex problem solving, and scenarios that benefit from explicit thinking traces.

  • Reasoning
  • Vision
  • Native PDF input
  • Tool Calling
  • Structured Output

Added Sep 29, 2025

Pricing

Auto routing · per 1M tokens
Input
$3.00
Output
$15.00
Cache read
$0.30
Compare provider prices

Specifications

Context window
200K
Max output
64K
Avg output (7d)
2.6K tokens
Longer than 95% of models

Benchmarks

Sourced from Vectara.

Hallucination Rate

12.0%

Hallucination Rate: 12.0
Better than 27% of models compared

Factual Consistency

88.0%

Factual Consistency: 88.0
Better than 27% of models compared

Answer Rate

95.6%

Answer Rate: 95.6
Better than 16% of models compared

Avg Summary Length

Average generated summary length

127.8

Last updated 2026-10-22 · Matched as anthropic/claude-sonnet-4-5-20250929

Vectara Leaderboard

Providers

Auto routing is available for this model. Explicit provider selection is not available.

Cache write /M
Auto
Auto
Recommended
$3.00$15.00$0.30$3.75N/AN/A
Batch API
ProviderInputOutputCached inputCache write
Anthropic
Anthropicclaude-sonnet-4-5-20250929-thinking
$1.50/M$7.50/M$0.15/M$1.88/M

Reliability

Related text models

Compare Claude Sonnet 4.5 Thinking with similar models from the same provider or model family.

Claude Sonnet 4.5

anthropic/claude-sonnet-4.5

Frontier‑level coding and agentic performance. Claude Sonnet 4.5 leads on real‑world coding tasks and shows substantial gains in computer use, reasoning, and math. Designed for long‑horizon, multi‑step work across IDE + terminal workflows, large codebases, and complex agents — a drop‑in upgrade over previous Sonnet versions.

Claude Sonnet 5.5

anthropic/claude-sonnet-5.5

Claude Sonnet 5.5 handles everyday coding, tool-based workflows, visual analysis, and polished writing with a 1M-token context window. This version skips up-front thinking and can reason between tool calls for faster responses; use Thinking for deeper planning and complex problems.

Claude Sonnet 5.5 Thinking

anthropic/claude-sonnet-5.5:thinking

Claude Sonnet 5.5 with adaptive thinking for complex coding, multi-step tool use, visual analysis, and detailed planning. Supports a 1M-token context window and five reasoning effort levels, with stronger thinking available when a task needs it.

Claude Sonnet 5

anthropic/claude-sonnet-5

Claude Sonnet 5 supports coding, agentic workflows, long-context reasoning, computer use, and practical knowledge work.

Claude Sonnet 5 Thinking

anthropic/claude-sonnet-5:thinking

Claude Sonnet 5 with adaptive thinking enabled for complex coding, planning, and agentic work.

Claude Sonnet Latest

anthropic/claude-sonnet-latest

Compatibility alias that routes to the newest version of Claude Sonnet. Currently routes to Claude Sonnet 5.5 Thinking.