tokevenGPTvsGPT
GPT 4.1 Nano vs GPT 5.1
Side-by-side comparison of pricing, task quality, and projected cost at higher scale.
Pricing
Side-by-side pricing
GPT 4.1 Nano
Fast / BudgetGPT 5.1
Mid-tierInput $/MTok
$0.10
$1.25
Output $/MTok
$0.40
$10.00
Cache discount
75% off
90% off
Context
1,047.576K
272K
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 4.1 Nano
GPT 5.1
Guidance
When to use GPT 4.1 Nano vs GPT 5.1
Choose GPT 4.1 Nano when...
- -Cost matters: 92% cheaper on input tokens
- -You need a larger context window (1,047.576K vs 272K)
Choose GPT 5.1 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 4.1 Nano
GPT 5.1
100K tokens
$0.02Cheaper
$0.39
1M tokens
$0.19Cheaper
$3.88
10M tokens
$1.90Cheaper
$38.75
FAQ
When should I use GPT 4.1 Nano instead of GPT 5.1?
GPT 4.1 Nano and GPT 5.1 perform similarly across all tracked tasks. Pick based on pricing and provider preference.
Is GPT 5.1 cheaper than GPT 4.1 Nano?
GPT 5.1 input costs $1.25/MTok, which is 1150% more than GPT 4.1 Nano at $0.10/MTok.
What are the context window sizes for GPT 4.1 Nano and GPT 5.1?
GPT 4.1 Nano has a 1,047.576K token context window. GPT 5.1 has a 272K 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 4.1 Nano and GPT 5.1 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.