Last verified 2025-09-22 (left) · 2025-09-22 (right)

GPT-5 nano vs o3 — Pricing & Capability Comparison

GPT-5 nano charges $0.05 per million input tokens and $0.40 per million output tokens. o3 comes in at $2.00 / $8.00. Context windows span 200K vs 200K tokens respectively.

TL;DR — Quick Comparison

  • GPT-5 nano is cheaper overall: $0.45 per 1M tokens (in+out) vs $10.00 for o3 — saves $9.55 per 1M tokens
  • Input pricing: GPT-5 nano $0.05/1M vs o3 $2.00/1M
  • Output pricing: GPT-5 nano $0.40/1M vs o3 $8.00/1M
  • Context window: GPT-5 nano offers more (200K vs 200K)
  • Use our calculator below to estimate costs for your specific usage pattern

Input price (per 1M)

GPT-5 nano

$0.05

o3

$2.00

GPT-5 nano leads here

Output price (per 1M)

GPT-5 nano

$0.40

o3

$8.00

GPT-5 nano leads here

Context window

GPT-5 nano

200,000 tokens

o3

200,000 tokens

GPT-5 nano leads here

Cached input

GPT-5 nano

Not published

o3

Not published

No published data

Cost comparison for 10K-token workloads

Side-by-side pricing for identical workloads (10,000 total tokens per request) across different distributions.

ScenarioGPT-5 nanoo3
Balanced conversation
50% input · 50% output
$0.0023$0.0500
Input-heavy workflow
80% input · 20% output
$0.0012$0.0320
Generation heavy
30% input · 70% output
$0.0030$0.0620
Cached system prompt
90% cached input · 10% fresh output
$0.0009$0.0260

Frequently asked questions

Which is cheaper: GPT-5 nano or o3?

GPT-5 nano is cheaper for input tokens at $0.05 per 1M tokens compared to $2.00. For output, GPT-5 nano costs $0.40 per 1M tokens versus $8.00 for o3.

What is the cost per 1M tokens for GPT-5 nano?

GPT-5 nano pricing: $0.05 per 1M input tokens and $0.40 per 1M output tokens. Context window: 200,000 tokens.

What is the cost per 1M tokens for o3?

o3 pricing: $2.00 per 1M input tokens and $8.00 per 1M output tokens. Context window: 200,000 tokens.

How much does it cost per 1K tokens?

Per 1K tokens: GPT-5 nano costs $0.0001 input / $0.0004 output. o3 costs $0.0020 input / $0.0080 output. This is useful for calculating small-scale usage costs.

Which model supports a larger context window?

GPT-5 nano offers 200,000 tokens (200K) versus 200K for o3.

What is the estimated monthly cost for typical usage?

For a typical workload of 10M input + 2M output tokens per month: GPT-5 nano would cost approximately $1.30, while o3 would cost $36.00. GPT-5 nano is more economical for this usage pattern.

Do these models support prompt caching?

GPT-5 nano does not publish cached pricing. o3 does not publish cached pricing.

Which model is best for my use case?

Choose GPT-5 nano for cost-sensitive applications with high input volume. Choose GPT-5 nano if you need 200K context for long documents or conversations. Consider prompt caching if you have repeated context. Use our token calculator to model your specific usage pattern.

Related resources

GPT-5 nano vs o3 Pricing (2025) — Cost per 1M Tokens Comparison | LLM Practical Experience Hub