ClaudevsGPT

Claude Mythos 5.1 vs GPT 5.6 Terra

Side-by-side comparison of pricing, task quality, and projected cost at higher scale.

Pricing

Side-by-side pricing

Claude Mythos 5.1

Flagship

GPT 5.6 Terra

Mid-tier
Input $/MTok
$10.00
$2.00
Output $/MTok
$50.00
$12.00
Cache discount
98% off
90% off
Context
1,000K
922K

Quality

Task confidence comparison

Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
0
vs
86
Code Review
0
vs
84
Summarization
0
vs
92
Q&A
0
vs
92
Extraction
0
vs
90
Reasoning
0
vs
82
Classification
0
vs
89
Creative Writing
0
vs
80
Claude Mythos 5.1
GPT 5.6 Terra

Guidance

When to use Claude Mythos 5.1 vs GPT 5.6 Terra

Choose Claude Mythos 5.1 when...

  • -You need a larger context window (1,000K vs 922K)
  • Similar performance; consider provider preference or ecosystem fit.

Choose GPT 5.6 Terra when...

  • -Cost matters: 80% cheaper on input tokens

At scale

Cost at scale

Estimated cost assuming a seventy percent input and thirty percent output token split.
Claude Mythos 5.1
GPT 5.6 Terra
100K tokens
$2.20
$0.50Cheaper
1M tokens
$22.00
$8.20Cheaper
10M tokens
$220.00
$82.00Cheaper

FAQ

When should I use Claude Mythos 5.1 instead of GPT 5.6 Terra?

Claude Mythos 5.1 and GPT 5.6 Terra perform similarly across all tracked tasks. Pick based on pricing and provider preference.

Is GPT 5.6 Terra cheaper than Claude Mythos 5.1?

Yes. GPT 5.6 Terra input costs $2.00/MTok vs $10.00/MTok for Claude Mythos 5.1, saving 80% on input.

What are the context window sizes for Claude Mythos 5.1 and GPT 5.6 Terra?

Claude Mythos 5.1 has a 1,000K token context window. GPT 5.6 Terra has a 922K token context window.

Track your real costs

Comparisons show estimated costs at list price. The dashboard reveals your real spend and savings.