Free Tool · Updated April 2026

AI API Cost Calculator

Estimate your monthly spend across OpenAI, Anthropic, and more. Enter your usage below — costs update instantly.

Your Usage
How many API requests your app makes daily
Input tokens
Output tokens
Estimated Cost OpenAI GPT-4o
Daily cost $0.00
Monthly cost $0.00
Yearly cost $0.00
Cost per 1,000 calls $0.00

Compare All Providers

Same workload, every model — ranked by monthly cost.

Model Daily Monthly Yearly
Current API Pricing (per 1M tokens)
GPT-4o
OpenAI
Input$2.50
Output$10.00
GPT-4
OpenAI
Input$30.00
Output$60.00
GPT-3.5 Turbo
OpenAI
Input$0.50
Output$1.50
Claude 3.5 Sonnet
Anthropic
Input$3.00
Output$15.00
Claude Opus 3
Anthropic
Input$15.00
Output$75.00
Claude 3 Haiku
Anthropic
Input$0.25
Output$1.25

Why Tracking Matters

Estimates are a starting point — real API costs drift. Usage spikes during marketing campaigns, agent loops can run unchecked, and model price changes don't always make the news. Teams that rely on manual spreadsheet estimates routinely discover their actual bill is 2–5× what they expected.

Proactive monitoring closes the gap. Setting up spend alerts takes five minutes and catches runaway costs before they hit your invoice. For teams running AI agent fleets, treating your AI spend like a budget line — with limits, alerts, and rollup visibility — is the difference between predictable costs and budget shock.

See how SpendPilot compares to other monitoring tools in our full comparison of AI cost monitoring platforms, or read the buyer's guide to AI cost monitoring tools.

SpendPilot monitors this automatically

Connect your OpenAI or Anthropic account once. Get real-time spend tracking, budget alerts, and cost anomaly detection — no spreadsheets required.

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