Ask

Claude Mythos 5 vs GPT-4o

Detailed pricing comparison and cost analysis.

Updated September 2026

Cost Simulator

Claude Mythos 5 Cost
$20.00
GPT-4o Cost
$4.50
GPT-4o is 78% cheaper
FeatureClaude Mythos 5GPT-4o
ProviderAnthropicOpenAI
Input Price (1M)$10.00$2.50
Output Price (1M)$50.00$10.00
Context Window1,000,000128,000

Verdict

Claude Mythos 5 costs $10.00 per 1M input tokens and $50.00 per 1M output tokens. GPT-4o costs $2.50 per 1M input tokens and $10.00 per 1M output tokens. GPT-4o is 75% cheaper on input tokens than Claude Mythos 5. For output tokens, GPT-4o is the more affordable option at $10.00/1M vs $50.00.

On context window, Claude Mythos 5 supports 1,000,000 tokens — meaning it can fit more conversation history, documents, or code in a single request. This matters for RAG pipelines, long document analysis, and agentic workflows where context builds up over many turns.

When to choose Claude Mythos 5

  • ✓ You need a larger context window (1,000,000 tokens)
  • ✓ You are already integrated with Anthropic

When to choose GPT-4o

  • ✓ You need the lowest input token cost ($ 2.50/1M)
  • ✓ Your workload is output-heavy — GPT-4o generates text cheaper
  • ✓ You are already integrated with OpenAI

Use the calculator above to simulate your specific workload and find the exact break-even point. For most applications, the cheapest model is the one that minimises your total monthly bill given your input-to-output token ratio.

Frequently Asked Questions

Is Claude Mythos 5 cheaper than GPT-4o?

GPT-4o is cheaper on input tokens at $2.50/1M vs $10.00/1M for Claude Mythos 5 — a 75% saving.

What is the context window of Claude Mythos 5 vs GPT-4o?

Claude Mythos 5 has a 1,000,000-token context window. GPT-4o has a 128,000-token context window. Claude Mythos 5 supports the larger context, suitable for longer documents and agentic workflows.

Which model is better: Claude Mythos 5 or GPT-4o?

The best choice depends on your use case. For cost efficiency on input tokens, GPT-4o is the cheaper option. For maximum context length, Claude Mythos 5 supports 1,000,000 tokens. Use the comparison table above to find the right fit for your workload.