GPT-4o Cost Calculator: OpenAI API pricing estimator
Estimate cost for GPT-4o. Adjust expected output tokens and call volume to forecast usage. Input $2.50/1M, output $10/1M (as of 2026).
GPT-4o pricing (per 1M tokens)
OpenAI charges per million tokens for GPT-4o. Output is 4x more expensive than input.
| Model | Input | Output | Context |
|---|---|---|---|
| GPT-4o | $2.50 | $10.00 | 128K |
What you'll use this for
Forecasting AI spend is the difference between a sustainable feature and an unexpected invoice. Pre-flight every prompt.
Budget planning
Forecast monthly and annual costs based on expected call volume and prompt size.
Model selection
Compare model size variants side-by-side to pick the right cost/quality tradeoff.
Cost optimization
See how prompt caching, shorter outputs, and smaller models slash bills.
Pricing transparency
All rates visible up front — no surprises after the invoice arrives.
How to estimate GPT costs
Paste your prompt
Drop a representative prompt into the left editor. Tokens are estimated at ~4 chars/token.
Set expected output tokens
How long do you expect the response to be? Default 500 covers a paragraph or two.
Set calls per day
How often does this prompt run? 100 = trial-scale, 10000+ = production-scale.
Read the forecast
Per-call, per-day, per-month, per-year totals update live as you tweak inputs.
Frequently asked questions
We use ~4 chars/token, accurate to about ±20%. For exact counts use the model-specific token counter such as the OpenAI token counter.
OpenAI's public pricing pages as of 2026. Subject to change — always confirm at openai.com/pricing before signing contracts.
Yes. Completely free, no signup, runs entirely in your browser.
Toggle "Cached input" to apply the model's published cached rate. OpenAI's prompt caching kicks in for repeated prefixes ≥ 1024 tokens and the discount is per-model (typically 50–87%). DeepSeek and Anthropic offer ~90% off cached input.
Provider tokenizers can differ slightly from our estimate; system prompts and tool definitions also count toward input; rates change over time. Treat this as a planning tool, not a billing replica.
About GPT-4o API pricing
GPT-4o is OpenAI's flagship multimodal model — text, vision, audio. At $2.50/1M input and $10/1M output, it sits in the middle of OpenAI's lineup: cheaper than GPT-5 but significantly more capable than GPT-4o mini.
When GPT-4o is the right pick
- You need vision or multimodal capability.
- You want strong reasoning at moderate cost.
- Your prompts fit in 128K context.
When to step down
- Bulk classification / extraction? GPT-4o mini at $0.15/1M input is 17x cheaper.
When to step up
- Complex multi-step reasoning, long-document synthesis, or 256K context needs? GPT-5.