High-volume, cost-sensitive work
Choose GPT-4 Turbo
GPT-4 Turbo costs 25% less on a typical mix of three input tokens for every output token ($15.00 against $20.00 per million tokens).
Claude Mythos 5.1 vs GPT-4 Turbo: price, context and capabilities
Choose Claude Mythos 5.1 for very long inputs and the latest release. Choose GPT-4 Turbo for high-volume, cost-sensitive work and writing and code generation.
In short
- GPT-4 Turbo is 25% cheaper than Claude Mythos 5.1 at the headline price ($15.00 / 1M tokens vs $20.00 / 1M tokens).
- Claude Mythos 5.1 reads more per request: 1M tokens against 128k.
- Claude Mythos 5.1 is the newer model (September 2026, against Apr 9, 2024).
- Only Claude Mythos 5.1 offers reasoning, prompt caching.
Which should you choose?
Each answer below comes straight from the published prices, specifications and independent benchmark results.
Writing and code generation
Choose GPT-4 Turbo
GPT-4 Turbo charges $30.00 per million output tokens, against $50.00 for Claude Mythos 5.1. Output dominates the bill when answers are long.
Very long inputs
Choose Claude Mythos 5.1
Claude Mythos 5.1 reads up to 1M tokens per request, against 128k for GPT-4 Turbo.
Latest release
Choose Claude Mythos 5.1
Claude Mythos 5.1 is the newer release (September 2026, against Apr 9, 2024 for GPT-4 Turbo).
Monthly cost at three volumes
| Volume | Claude Mythos 5.1 | GPT-4 Turbo | Difference |
|---|---|---|---|
| Prototype: 1M input, 250K output tokens | $22.50 | $17.50 | GPT-4 Turbo, $5.00 less |
| Production: 20M input, 5M output tokens | $450.00 | $350.00 | GPT-4 Turbo, $100.00 less |
| Scale: 500M input, 100M output tokens | $10,000 | $8,000 | GPT-4 Turbo, $2,000 less |
Standard rates, without caching or batch discounts. Volumes are per month.
Specifications side by side
| Claude Mythos 5.1 | GPT-4 Turbo | |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Category | Language models | Language models |
| Status | Generally available · Limited access | Deprecated |
| Headline price | $20.00 / 1M tokens | $15.00 / 1M tokens |
| Input | $10.00 / 1M tokens | $10.00 / 1M tokens |
| Output | $50.00 / 1M tokens | $30.00 / 1M tokens |
| Cached input | $0.25 / 1M tokens | No data |
| Context window | 1M | 128k |
| Max output | 128k | 4k |
| Released | September 2026 | Apr 9, 2024 |
| Knowledge cutoff | No data | December 2023 |
| Licence | Proprietary | Proprietary |
| Capabilities | Vision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API | Vision, Tool calling, Structured output, Batch API |
| API model id | claude-mythos-5-1 | gpt-4-turbo |
Benchmarks side by side
Leader in bold.
| Benchmark | Claude Mythos 5.1 | GPT-4 Turbo |
|---|---|---|
| Humanity's Last Exam | No data | 3.1% |
Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.
Frequently asked questions
Should I choose Claude Mythos 5.1 or GPT-4 Turbo?
Choose Claude Mythos 5.1 for very long inputs and the latest release. Choose GPT-4 Turbo for high-volume, cost-sensitive work and writing and code generation.
Which is cheaper, Claude Mythos 5.1 or GPT-4 Turbo?
GPT-4 Turbo is 25% cheaper than Claude Mythos 5.1 at the headline price ($15.00 / 1M tokens vs $20.00 / 1M tokens).
Which has the larger context window, Claude Mythos 5.1 or GPT-4 Turbo?
Claude Mythos 5.1 reads more per request: 1M tokens against 128k.
What is the difference between Claude Mythos 5.1 and GPT-4 Turbo?
Claude Mythos 5.1 is made by Anthropic and GPT-4 Turbo by OpenAI. GPT-4 Turbo is 25% cheaper than Claude Mythos 5.1 at the headline price ($15.00 / 1M tokens vs $20.00 / 1M tokens). Claude Mythos 5.1 reads more per request: 1M tokens against 128k. Claude Mythos 5.1 is the newer model (September 2026, against Apr 9, 2024). Only Claude Mythos 5.1 offers reasoning, prompt caching.
How much do Claude Mythos 5.1 and GPT-4 Turbo cost per month?
At 20 million input and 5 million output tokens a month, Claude Mythos 5.1 costs $450.00 and GPT-4 Turbo costs $350.00, at standard rates.
Which is newer, Claude Mythos 5.1 or GPT-4 Turbo?
Claude Mythos 5.1 was released on September 2026 and GPT-4 Turbo on Apr 9, 2024.