ClaudevsGPT

Claude Opus 5 vs o3

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

Pricing

Side-by-side pricing

Claude Opus 5

Flagship

o3

Mid-tier
Input $/MTok
$5.00
$2.00
Output $/MTok
$25.00
$8.00
Cache discount
90% off
75% off
Context
1,000K
200K

Quality

Task confidence comparison

Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
0
vs
0
Code Review
0
vs
0
Summarization
0
vs
0
Q&A
0
vs
0
Extraction
0
vs
0
Reasoning
0
vs
0
Classification
0
vs
0
Creative Writing
0
vs
0
Claude Opus 5
o3

Guidance

When to use Claude Opus 5 vs o3

Choose Claude Opus 5 when...

  • -You need a larger context window (1,000K vs 200K)
  • Similar performance; consider provider preference or ecosystem fit.

Choose o3 when...

  • -Cost matters: 60% cheaper on input tokens

At scale

Cost at scale

Estimated cost assuming a seventy percent input and thirty percent output token split.
Claude Opus 5
o3
100K tokens
$1.10
$0.38Cheaper
1M tokens
$11.00
$3.80Cheaper
10M tokens
$110.00
$38.00Cheaper

FAQ

When should I use Claude Opus 5 instead of o3?

Claude Opus 5 and o3 perform similarly across all tracked tasks. Pick based on pricing and provider preference.

Is o3 cheaper than Claude Opus 5?

Yes. o3 input costs $2.00/MTok vs $5.00/MTok for Claude Opus 5, saving 60% on input.

What are the context window sizes for Claude Opus 5 and o3?

Claude Opus 5 has a 1,000K token context window. o3 has a 200K token context window.

Track your real costs

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