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

GPT-5 Chat vs o4-mini — Pricing & Capability Comparison

GPT-5 Chat charges $1.25 per million input tokens and $10.00 per million output tokens. o4-mini comes in at $1.10 / $4.40. Context windows span 200K vs 200K tokens respectively.

TL;DR — Quick Comparison

✓o4-mini is cheaper overall: $5.50 per 1M tokens (in+out) vs $11.25 for GPT-5 Chat — saves $5.75 per 1M tokens
✓Input pricing: GPT-5 Chat $1.25/1M vs o4-mini $1.10/1M
✓Output pricing: GPT-5 Chat $10.00/1M vs o4-mini $4.40/1M
✓Context window: GPT-5 Chat offers more (200K vs 200K)
✓Use our calculator below to estimate costs for your specific usage pattern

Input price (per 1M)

GPT-5 Chat

$1.25

o4-mini

$1.10

o4-mini leads here

Output price (per 1M)

GPT-5 Chat

$10.00

o4-mini

$4.40

o4-mini leads here

Context window

GPT-5 Chat

200,000 tokens

o4-mini

200,000 tokens

GPT-5 Chat leads here

Cached input

GPT-5 Chat

$0.125

o4-mini

Not published

GPT-5 Chat leads here

Which one should you choose?

Skip the spreadsheet if you just need the practical takeaway. Use these rules when deciding between GPT-5 Chat and o4-mini.

Choose o4-mini if input tokens dominate your bill

o4-mini has the lower input rate, which usually matters most for chat, RAG, classification, and long-prompt workflows where prompt volume stays much larger than generated output.

Choose o4-mini if you generate long answers

o4-mini is cheaper on output tokens, so it tends to win for report generation, coding assistance, reasoning traces, and any workflow where completions are long.

Choose GPT-5 Chat if context size is the blocker

GPT-5 Chat offers the larger published context window, which is more important than small pricing differences when you need to fit large files, long chats, or multi-document prompts into one request.

Cost comparison for 10K-token workloads

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

Scenario	GPT-5 Chat	o4-mini	GPT-5 Chat cached
Balanced conversation 50% input · 50% output	$0.0563	$0.0275	$0.0506
Input-heavy workflow 80% input · 20% output	$0.0300	$0.0176	$0.0210
Generation heavy 30% input · 70% output	$0.0738	$0.0341	$0.0704
Cached system prompt 90% cached input · 10% fresh output	$0.0212	$0.0143	$0.0111

Frequently asked questions

Which is cheaper: GPT-5 Chat or o4-mini?

o4-mini is cheaper for input tokens at $1.10 per 1M tokens compared to $1.25. For output, o4-mini costs $4.40 per 1M tokens versus $10.00 for GPT-5 Chat.

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

GPT-5 Chat pricing: $1.25 per 1M input tokens and $10.00 per 1M output tokens. Context window: 200,000 tokens.

What is the cost per 1M tokens for o4-mini?

o4-mini pricing: $1.10 per 1M input tokens and $4.40 per 1M output tokens. Context window: 200,000 tokens.

How much does it cost per 1K tokens?

Per 1K tokens: GPT-5 Chat costs $0.0013 input / $0.0100 output. o4-mini costs $0.0011 input / $0.0044 output. This is useful for calculating small-scale usage costs.

Which model supports a larger context window?

GPT-5 Chat offers 200,000 tokens (200K) versus 200K for o4-mini.

What is the estimated monthly cost for typical usage?

For a typical workload of 10M input + 2M output tokens per month: GPT-5 Chat would cost approximately $32.50, while o4-mini would cost $19.80. o4-mini is more economical for this usage pattern.

Do these models support prompt caching?

GPT-5 Chat supports prompt caching at $0.125 per 1M cached tokens, reducing costs for repeated context by up to 90%. o4-mini does not publish cached pricing.

Which model is best for my use case?

Choose o4-mini for cost-sensitive applications with high input volume. Choose GPT-5 Chat 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.