ClaudevsGPT

Claude Mythos 5.1 vs GPT 5.4

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 5.4

Mid-tier
Input $/MTok
$10.00
$2.50
Output $/MTok
$50.00
$15.00
Cache discount
98% off
90% off
Context
1,000K
1,050K

Quality

Task confidence comparison

Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
0
vs
84
Code Review
0
vs
82
Summarization
0
vs
91
Q&A
0
vs
91
Extraction
0
vs
89
Reasoning
0
vs
80
Classification
0
vs
88
Creative Writing
0
vs
78
Claude Mythos 5.1
GPT 5.4

Guidance

When to use Claude Mythos 5.1 vs GPT 5.4

Choose Claude Mythos 5.1 when...

  • Similar performance; consider provider preference or ecosystem fit.

Choose GPT 5.4 when...

  • -Cost matters: 75% cheaper on input tokens
  • -You need a larger context window (1,050K vs 1,000K)

At scale

Cost at scale

Estimated cost assuming a seventy percent input and thirty percent output token split.
Claude Mythos 5.1
GPT 5.4
100K tokens
$2.20
$0.63Cheaper
1M tokens
$22.00
$10.25Cheaper
10M tokens
$220.00
$102.50Cheaper

FAQ

When should I use Claude Mythos 5.1 instead of GPT 5.4?

Claude Mythos 5.1 and GPT 5.4 perform similarly across all tracked tasks. Pick based on pricing and provider preference.

Is GPT 5.4 cheaper than Claude Mythos 5.1?

Yes. GPT 5.4 input costs $2.50/MTok vs $10.00/MTok for Claude Mythos 5.1, saving 75% on input.

What are the context window sizes for Claude Mythos 5.1 and GPT 5.4?

Claude Mythos 5.1 has a 1,000K token context window. GPT 5.4 has a 1,050K token context window.

Track your real costs

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