Near-Opus quality at a permanent $2/$10 — Anthropic cancelled the planned September price increase. The default Claude for most production work.
$2 / 1M input and $10 / 1M output started as introductory pricing through August 31, 2026, but on August 10, 2026 Anthropic made it the permanent standard rate — the scheduled increase to $3/$15 will not happen.
Released June 30, 2026, Sonnet 5 is the model Anthropic expects most developers to run by default, and it's the free-tier model in Claude.ai. It launched at $3/$15 per 1M tokens standard, with an introductory $2/$10 rate through August 31, 2026. On August 10, 2026, Anthropic reversed course: the $2/$10 rate became the permanent standard price, and the planned September 1 increase to $3/$15 was formally cancelled. Sonnet 5 now sits meaningfully cheaper than its launch pricing implied, on a permanent basis.
The Sonnet pitch is otherwise unchanged in shape: most of Opus's capability at a meaningful discount, with better latency. What moved in Sonnet 5 versus earlier Sonnets is the quality ceiling — long-horizon agent loops, tool use, and structured code edits are materially better, while the 1M context window keeps Sonnet competitive with GPT-5.4 for repo-scale work.
Sonnet 5 is a strong all-rounder: writing, code, vision, and structured extraction. It's the right model for production chat agents and coding assistants because answers stay composed under load, and tool use is reliable across multi-turn loops. Compared with the previous Sonnet generation, the biggest gains are in agentic execution — fewer dropped instructions and cleaner self-verification on longer tasks.
Where it still trails the Opus tier (Opus 5): the hardest novel reasoning, agentic coding, and the most demanding long-document synthesis. Where it trails GPT-5.5: outright token throughput.
| Model | Input / 1M | Output / 1M | Context |
|---|---|---|---|
| Claude Sonnet 5 | $2 | $10 | 1M |
| Claude Opus 5 | $5 | $25 | 1M |
| Claude Haiku 4.5 | $1 | $5 | 200K |
| GPT-5.4 | $2.50 | $15 | 272K |
Sonnet 5's now-permanent $2/$10 rate makes it a clear mid-tier value pick — cheaper on output than GPT-5.4, with a full 1M context window. Opus 5 costs 2.5x more for the highest-stakes work; Haiku 4.5 is half the price for narrower tasks.