Tools

Free tools.

Small, fast calculators for founders and marketers — built by a senior engineer, no sign-up, no email wall. Every one shows its formula so you can trust the number.

Business

Margin calculator

Profit margin, markup, and discount in one tool. Enter cost and price, get the margin — or work backwards.

Marketing

CPM calculator

Cost per thousand impressions, solved any direction. Plug in two of cost, impressions, or CPM.

SaaS

LTV : CAC calculator

Customer lifetime value, CAC payback, and the 3:1 ratio benchmark for SaaS — instantly.

Engineering

Software cost calculator

What an MVP, SaaS, or custom build actually costs in 2026, against US/EU agency benchmarks.

Need something custom built — not just measured? See how I work →

Contact

Let's build something great.

Open to Senior, Staff, and Founding Engineer roles — and select freelance engagements. Reply within 24 hours, CET timezone.

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