tokevenGPTvsGPT
GPT 5 Nano vs o3 Pro
Side-by-side comparison of pricing, task quality, and projected cost at higher scale.
Pricing
Side-by-side pricing
GPT 5 Nano
Fast / Budgeto3 Pro
FlagshipInput $/MTok
$0.05
$20.00
Output $/MTok
$0.40
$80.00
Cache discount
90% off
0% off
Context
272K
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
GPT 5 Nano
o3 Pro
Guidance
When to use GPT 5 Nano vs o3 Pro
Choose GPT 5 Nano when...
- -Cost matters: 100% cheaper on input tokens
- -You need a larger context window (272K vs 200K)
Choose o3 Pro when...
- Similar performance; consider provider preference or ecosystem fit.
At scale
Cost at scale
Estimated cost assuming a seventy percent input and thirty percent output token split.
GPT 5 Nano
o3 Pro
100K tokens
$0.02Cheaper
$3.80
1M tokens
$0.15Cheaper
$38.00
10M tokens
$1.55Cheaper
$380.00
FAQ
When should I use GPT 5 Nano instead of o3 Pro?
GPT 5 Nano and o3 Pro perform similarly across all tracked tasks. Pick based on pricing and provider preference.
Is o3 Pro cheaper than GPT 5 Nano?
o3 Pro input costs $20.00/MTok, which is 39900% more than GPT 5 Nano at $0.05/MTok.
What are the context window sizes for GPT 5 Nano and o3 Pro?
GPT 5 Nano has a 272K token context window. o3 Pro has a 200K token context window.
Go deeper on either model
Per-call cost calculators, provider lineups, and price history for both models on this page.
Other comparisons
How GPT 5 Nano and o3 Pro stack up against the rest of the field.
Track your real costs
Comparisons show estimated costs at list price. The dashboard reveals your real spend and savings.