Free tools for AI & infrastructure cost.
Practical, no-signup tools that help you estimate and reduce what your product costs to run — built by the team that does this for clients.
LLM / AI API cost calculator
Estimate your monthly AI API bill from tokens-per-request and volume, compare Claude / GPT-4o / other models side by side, and see how much model routing and prompt caching could save. Every price is editable.
Open the calculator →Microservices vs monolith decision tool
Answer 7 questions and get an honest, weighted recommendation — monolith, modular monolith, or microservices — with the exact signals behind it. Most startups don't need microservices yet; this tells you if you're one that does.
Get my recommendation →AI cost-per-user & margin calculator
Enter your per-user AI usage and what you charge to see your AI cost per user, gross margin, and whether your AI feature is actually profitable.
Check my margin →Token count & cost estimator
Paste any prompt or text to estimate its token count and the cost to run it across Claude, GPT-4o and other models — per call and per month.
Estimate tokens →Cloud cost-to-scale estimator
Estimate your monthly infrastructure cost from users and usage, then project it at 10× and 100× scale — compute, database and bandwidth, all editable.
Project my bill →Server capacity calculator
Enter peak traffic and per-request latency to get how many server instances you need — with utilization headroom so you're not at the redline.
Size my fleet →Concurrency & throughput calculator
Little's Law in your browser: convert between requests per second, latency and concurrent in-flight requests — plus a concurrent-users-to-RPS helper.
Run the numbers →Database connection pool calculator
Size your connection pool from peak load and query time — and find out whether you're connection-starved or about to exhaust your database's limit.
Size my pool →Caching ROI calculator
Estimate the monthly cost and latency a cache would save on a hot path — and whether it pays for itself — from volume, hit rate and backend cost.
Is it worth it? →Uptime / SLA downtime calculator
Convert any availability target like 99.9% into allowed downtime per day, week, month and year — and back again — plus your monthly error budget.
Calculate downtime →Microservices readiness scorecard
Score your readiness across CI/CD, testing, observability, on-call and IaC — and see the specific gaps to close before you split into services.
Score my readiness →Cost-of-a-rewrite estimator
Put a number on a re-architecture — direct engineering cost plus the opportunity cost of features you won't ship — so you can weigh it against designing for scale up front.
Estimate the cost →More tools coming soon. Want one built? Tell us what would help.