Claude Sonnet 5 vs GPT-5.4
Side-by-side comparison of pricing, context window, modalities, licensing, and strengths — with practical guidance on which model fits which workload.
| Spec | Claude Sonnet 5 | GPT-5.4 |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Context window | 1M tokens | 1M tokens |
| Input price (per 1M tokens) | $3.00 | $2.50 |
| Output price (per 1M tokens) | $15.00 | $15.00 |
| Example workload (10M in + 2M out) | $60.00 / month | $55.00 / month |
| Modalities | text, image, code | text, image, code |
| Knowledge cutoff | Not disclosed | Not disclosed |
| Release date | 2026 | 2026 |
| License | Proprietary | Proprietary |
| Strengths | Coding, Agentic work, 1M context, Intro pricing ($2/$10 to Aug 2026) | Coding, Tool search, Structured output, Price-performance |
| Open weights | No | No |
Verdict
The workhorse matchup most production teams actually face. Both are the “90% of the flagship at half the price” tier: Claude Sonnet 5 lists at $3/$15 (with introductory $2/$10 pricing through August 2026), GPT-5.4 at $2.50/$15 — but GPT-5.4’s input price doubles past 272K tokens, while Sonnet 5’s 1M context carries no surcharge. Sonnet 5 reaches near-Opus quality on coding and agentic benchmarks; GPT-5.4 adds tool search for large tool libraries and OpenAI’s mature structured-output guarantees.
When to choose Claude Sonnet 5
Pick Claude Sonnet 5 for coding agents, big-context work at flat pricing, and the discounted intro rate while it lasts.
When to choose GPT-5.4
Pick GPT-5.4 for apps with many tools (tool search), strict JSON pipelines, and drop-in OpenAI SDK compatibility.
Prices and specs reflect published provider information and change frequently — always confirm on the provider's pricing page before committing to a workload.
Frequently asked questions
Which is cheaper: Claude Sonnet 5 or GPT-5.4?
GPT-5.4 is cheaper per token: $2.50 input / $15.00 output per 1M tokens, versus $3.00 / $15.00 for Claude Sonnet 5. Actual costs depend on your input-to-output ratio — try the AI cost calculator for your own numbers.
Which has the larger context window?
GPT-5.4 supports 1M tokens versus 1M for Claude Sonnet 5 — roughly 1.1× more room for documents, code, and conversation history.
Can I self-host either model?
No — both models are proprietary and available only through their providers' APIs or cloud platforms.
How should I test which model is better for my use case?
Benchmarks are a starting point, not an answer. Run both models on 20–50 examples of your real task and compare outputs blind. Use our token counter to estimate prompt sizes and the cost calculator to project monthly spend before committing.