Free tool

LLM API Cost Calculator

Estimate your monthly OpenAI, Anthropic, and Google Gemini API spend. Compare the same workload across models and see what prompt caching would save. Prices from official provider pricing pages, verified 2026-05-20.

Total monthly cost
$0.00
Annualized
$0.00
Prompt caching saves you
$0.00
vs the same workload with 0% cached input

Same workload on other models

Your combined traffic priced on every model, cheapest first. This is the arithmetic behind model routing: many workloads run fine on a model several rows further down.

Provider Model Monthly cost vs your selection

This math, live on your real traffic

SpendProxy sits in front of your AI APIs inside your own VPC, tracks every request at billing accuracy, and runs optimization engines — prompt cache injection, model routing, dedup, budget guardrails — on traffic you approve.

Current LLM API pricing reference

Per million tokens, from official provider pricing pages as of 2026-05-20. Cached input is the provider's cache-read rate (requires prompt caching to be set up correctly).

Provider Model Input / 1M Cached input / 1M Output / 1M
OpenAI gpt-5.5 $5.00 $0.500 $30.00
OpenAI gpt-5.5-pro $30.00 $180.00
OpenAI gpt-5.4 $2.50 $0.250 $15.00
OpenAI gpt-5.4-mini $0.75 $0.075 $4.50
OpenAI gpt-5.4-nano $0.20 $0.020 $1.25
OpenAI gpt-5.3-codex $1.75 $0.175 $14.00
OpenAI gpt-4.1 $2.00 $0.500 $8.00
OpenAI gpt-4.1-mini $0.40 $0.100 $1.60
OpenAI gpt-4.1-nano $0.10 $0.025 $0.40
OpenAI gpt-4o $2.50 $1.250 $10.00
OpenAI gpt-4o-mini $0.15 $0.075 $0.60
OpenAI o3 $2.00 $0.200 $8.00
OpenAI o3-mini $1.10 $0.275 $4.40
OpenAI o4-mini $0.55 $0.055 $2.20
Anthropic claude-opus-4-7 $5.00 $0.500 $25.00
Anthropic claude-sonnet-4-6 $3.00 $0.300 $15.00
Anthropic claude-haiku-4-5 $1.00 $0.100 $5.00
Anthropic claude-opus-4-1 $15.00 $1.500 $75.00
Google gemini-3.1-pro $2.00 $0.200 $12.00
Google gemini-3.5-flash $1.50 $0.150 $9.00
Google gemini-3.1-flash-lite $0.25 $0.025 $1.50
Google gemini-2.5-pro $1.25 $0.125 $10.00
Google gemini-2.5-flash $0.30 $0.030 $2.50
Google gemini-2.5-flash-lite $0.10 $0.010 $0.40

Notes: reasoning/thinking-token surcharges, batch discounts, long-context tier pricing, and cache-write fees are not modeled — actual bills vary with workload shape. Prices change; when they do, this page is updated from the same pricing database that powers SpendProxy's cost engine.