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OpenAI Token Cost Calculator

Calculate OpenAI API token costs for every current GPT model, from GPT-5.6 Luna to GPT-5.6 Sol.

Usage

$0.15/M in · $0.075/M cached in · $0.60/M out · 128K context

Estimated cost

$13.50/month

Per request

$0.00045

Per day

$0.45

Per year

$164.25

Compare across models

ModelProviderPer month
OpenAI$7.50
OpenAI$13.50
OpenAI$24.00
OpenAI$36.00
OpenAI$37.50
OpenAI$37.50
Google$46.50
Google$78.75
Anthropic$105.00
OpenAI$180.00
OpenAI$180.00
Google$180.00
OpenAI$187.50
Anthropic$210.00
OpenAI$225.00
OpenAI$240.00
Google$240.00
Anthropic$315.00
OpenAI$420.00
Anthropic$525.00
Anthropic$525.00
Anthropic$525.00
Anthropic$1,050.00

How this is calculated

Providers bill input and output tokens separately, per million tokens (MTok). Cached input tokens — a repeated prompt prefix the provider recognizes — are billed at a discounted rate.

cost = (input_tokens − cached_tokens) × input_rate
     + cached_tokens × cached_rate
     + output_tokens × output_rate

Pricing is verified against provider pricing pages as of 2026-09-01. AI and cloud pricing changes frequently — confirm the current rate on the provider's own pricing page before budgeting.

Frequently asked questions

How many tokens is my prompt?

As a rule of thumb, 1 token ≈ 4 characters ≈ ¾ of a word in English. For exact counts, use OpenAI's tokenizer or the `tiktoken` library — this calculator takes token counts as input rather than raw text.

What's the price difference between GPT-5.6 tiers?

GPT-5.6 Sol, Terra, and Luna are priced roughly 20x apart between the cheapest and most capable tier — Luna costs $0.20/$1.20 per million input/output tokens, Sol costs $4.00/$20.00.

Does OpenAI charge for cached tokens?

Yes, at a discount — repeated prompt prefixes (like a fixed system prompt) are automatically detected and billed at the cached input rate, roughly 10% of the standard input rate, with no code changes required.

Are older models like GPT-3.5 still cheaper?

GPT-3.5 Turbo remains inexpensive but is now a legacy model; GPT-5-nano and GPT-5.6 Luna are comparably priced with significantly better capability for most tasks.