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

GPT-5 nano vs o3-pro — Pricing & Capability Comparison

GPT-5 nano charges $0.05 per million input tokens and $0.40 per million output tokens. o3-pro comes in at $20.00 / $80.00. Context windows span 200K vs 200K tokens respectively.

Input price (per 1M)

GPT-5 nano

$0.05

o3-pro

$20.00

GPT-5 nano leads here

Output price (per 1M)

GPT-5 nano

$0.40

o3-pro

$80.00

GPT-5 nano leads here

Context window

GPT-5 nano

200,000 tokens

o3-pro

200,000 tokens

GPT-5 nano leads here

Cached input

GPT-5 nano

Not published

o3-pro

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-pro
Balanced conversation
50% input · 50% output
$0.0023$0.500
Input-heavy workflow
80% input · 20% output
$0.0012$0.320
Generation heavy
30% input · 70% output
$0.0030$0.620
Cached system prompt
90% cached input · 10% fresh output
$0.0009$0.260

Frequently asked questions

Which model is cheaper per million input tokens?

GPT-5 nano costs $0.05 per million input tokens versus $20.00 for o3-pro.

How do output prices compare?

GPT-5 nano charges $0.40 per million output tokens, while o3-pro costs $80.00 per million.

Which model supports a larger context window?

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

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