Claude Mythos 5 vs GPT-6 Astra: price, context and capabilities

Choose GPT-6 Astra for the latest release; on the other points the two are level or the data is missing.

In short

  • Both cost the same at the headline price ($20.00 / 1M tokens).
  • GPT-6 Astra reads more per request: 1.05M tokens against 1M.
  • GPT-6 Astra is the newer model (Sep 3, 2026, against June 2026).

Open in the full comparison table

What a month costsAt 20 million input and 5 million output tokens a month.
  1. Claude Mythos 5Anthropic$450
  2. GPT-6 AstraOpenAI$450

Try your own volumes in the calculator

Which should you choose?

Each answer below comes straight from the published prices, specifications and independent benchmark results.

High-volume, cost-sensitive work

Either one

Both cost $20.00 per million tokens on a typical mix of three input tokens for every output token.

Latest release

Choose GPT-6 Astra

GPT-6 Astra is the newer release (Sep 3, 2026, against June 2026 for Claude Mythos 5).

Monthly cost at three volumes

VolumeClaude Mythos 5GPT-6 AstraDifference
Prototype: 1M input, 250K output tokens $22.50 $22.50 =
Production: 20M input, 5M output tokens $450.00 $450.00 =
Scale: 500M input, 100M output tokens $10,000 $10,000 =

Standard rates, without caching or batch discounts. Volumes are per month.

Specifications side by side

Claude Mythos 5GPT-6 Astra
ProviderAnthropicOpenAI
CategoryLanguage modelsLanguage models
StatusLegacy · Limited accessGenerally available
Headline price$20.00 / 1M tokens$20.00 / 1M tokens
Input$10.00 / 1M tokens$10.00 / 1M tokens
Output$50.00 / 1M tokens$50.00 / 1M tokens
Cached input$1.00 / 1M tokens$1.00 / 1M tokens
Context window1M1.05M
Max output128k128k
ReleasedJune 2026Sep 3, 2026
Knowledge cutoffNo dataApril 2026
LicenceProprietaryProprietary
CapabilitiesVision, Reasoning, Tool calling, Structured output, Prompt caching, Batch APIVision, Reasoning, Tool calling, Structured output, Prompt caching, Batch API
API model idclaude-mythos-5gpt-6-astra

Benchmarks side by side

Leader in bold.

BenchmarkClaude Mythos 5GPT-6 Astra
Intelligence Index No data 52.7
SciCode No data 56.5%
GPQA Diamond No data 96.1%
Humanity's Last Exam No data 54.7%
MMMU-Pro (visual reasoning) No data 86.9%
Long-context reasoning (AA-LCR) No data 80.7%

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 or GPT-6 Astra?

Choose GPT-6 Astra for the latest release; on the other points the two are level or the data is missing.

Which is cheaper, Claude Mythos 5 or GPT-6 Astra?

Both cost the same at the headline price ($20.00 / 1M tokens).

Which has the larger context window, Claude Mythos 5 or GPT-6 Astra?

GPT-6 Astra reads more per request: 1.05M tokens against 1M.

What is the difference between Claude Mythos 5 and GPT-6 Astra?

Claude Mythos 5 is made by Anthropic and GPT-6 Astra by OpenAI. Both cost the same at the headline price ($20.00 / 1M tokens). GPT-6 Astra reads more per request: 1.05M tokens against 1M. GPT-6 Astra is the newer model (Sep 3, 2026, against June 2026).

How much do Claude Mythos 5 and GPT-6 Astra cost per month?

At 20 million input and 5 million output tokens a month, Claude Mythos 5 costs $450.00 and GPT-6 Astra costs $450.00, at standard rates.

Which is newer, Claude Mythos 5 or GPT-6 Astra?

GPT-6 Astra was released on Sep 3, 2026 and Claude Mythos 5 on June 2026.