AI API Prompt Budget & Monthly Spend Forecaster
Forecast monthly and annual API infrastructure costs based on daily active users, requests per user, average prompt length, and cached token discounts.
1. Traffic & Usage Parameters
2. Model & Architecture Tuning
Applies 50% - 90% discount to cached input tokens on repeated system prompts and RAG contexts.
Used to compute SaaS gross margin after AI compute costs.
10,000 queries/day across active users
450M Input | 120M Output
Reduced input cost by 35%
What-If Cost Optimization Scenarios
See how your monthly burn changes if you route traffic or background workers to high-efficiency models.
| Model Architecture | Monthly API Burn | Annual Burn | Cost / User / Mo | Monthly Difference | Runway Impact |
|---|
Recommended Breakeven Subscription:
To maintain a healthy 75% gross SaaS software margin, charge at least $9.20/month per active subscriber.
Production Optimization Recommendation:
Use prompt caching and consider a dual-model tiering pattern: route 80% of classification and simple queries to a low-cost model (e.g. GPT-4o-mini or Gemini 1.5 Flash) and reserve flagship models for complex reasoning.
Informational & Educational Disclaimer
This tool is designed for informational and educational estimation purposes only. Calculations are based on user-provided inputs and standard mathematical formulas. For official tax, legal, or financial decisions, please consult certified professionals or official government publications.
Tool Under Active Refinement
This tool is currently an early prototype undergoing active improvement. It is being furnished and polished for improved performance, accuracy, and functionality, and will be fully furnished soon.