LLM ModelsPaid
Claude Sonnet 4.5
The perfect balance of speed and intelligence.
Claude Sonnet 4.5 (Sep 2025) balances Opus-level reasoning with Sonnet-level speed, making it the default choice for most agentic coding tasks.
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Overview
Claude 3.5 Sonnet -> Claude Sonnet 4.5 (Sep 2025)
Rating: 9.7/10 (The Workhorse)
1. Executive Summary
Released in September 2025, Claude Sonnet 4.5 quickly became the default model for most developers. It balances the reasoning depth of Opus with the speed of Sonnet.
2. Key Improvements
- Coding Performance: 80.2% on SWE-bench (Verified).
- Context: 200k tokens with near-perfect recall.
- Cost: Significantly cheaper than Opus 4.5 while beating GPT-5 in many coding benchmarks.
