I built a free API cost calculator after a $340 surprise invoice

Name: I built a free API cost calculator after a $340 surprise invoice
Availability: InStock
Author: chnbydigi

by chnbydigi·Jun 18, 2026·1 point·0 comments

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AI Analysis

●MidSolve My Problem

Free browser-based infra cost calculators when provider tools already exist.

Strengths

•Client-side execution means zero data sent anywhere, genuine privacy
•Consolidates 12 different calculator types in one place instead of scattered tools
•2026 pricing claims suggest active maintenance of rate cards

Weaknesses

•Provider-specific calculators (AWS, OpenAI) already offer this with more accuracy
•No volume discounts, caching, or batch pricing support limits real-world utility

Post Description

I was building a small LLM-powered side project and forgot to account for my system prompt tokens. 800 tokens × 2,000 requests/day × input token rate = $340 invoice I wasn't expecting.

Built APICalculators to avoid doing this math in spreadsheets every time. It now covers 16 calculators: LLM APIs (GPT-4o, Claude, Gemini), vector databases (Pinecone, Qdrant, Supabase), serverless (Lambda, Cloudflare Workers), auth providers (Clerk, Auth0), payment processors (Stripe vs Paddle), and cloud VPS comparison.

Everything runs in the browser — no signup, no data sent anywhere.

Would love feedback on what's missing or wrong.