CalcLab
22 tools · 2026 edition · Privacy-first

Calculators that actually explain themselves.

22 fast, accurate tools across health, finance, construction, education, and developer workflows. Every formula sourced. Every result shown step-by-step. Files never leave your device.

  • Privacy-first
  • Sub-second loads
  • Math always shown
  • Open formulas
Most used

Featured tools

Hand-picked across health, finance, building, and dev — the tools that earn their place in your bookmarks.

Categories

Browse by category

Six clusters. 22 tools. All free, all explained.

Finance

Mortgages, margins, salary, loans, investing — fast answers with the math shown.

All 5 finance tools →

Health & Fitness

Macros, calories, weight, pregnancy, peptides — backed by primary research.

All 5 health & fitness tools →

Construction & Home

Concrete, gravel, fence posts, solar — built for contractors and homeowners.

All 4 construction & home tools →

Education

GPA and grade tools that answer the question students actually ask.

All 3 education tools →

Developer Tools

Practical calculators for builders — token costs, latency, conversions.

All 2 developer tools tools →

Writers Tools

Manuscript formatting, ebook export, and writer-grade utilities for self-publishers.

All 1 writers tools tools →

File Converters

Privacy-first, in-browser converters. Your files never leave your device.

All 2 file converters tools →
Methodology

Every formula. Every source. Public.

We follow Google's E-E-A-T standards. Each tool cites peer-reviewed papers, government guidelines, or vendor documentation. Reviewed annually. No black boxes.

Read methodology
  • 01
    Sourced. Every formula links a primary reference.
  • 02
    Reviewed. Domain experts approve each tool annually.
  • 03
    Open. Math is shown, not hidden behind a wall.
  • 04
    Private. Converters run in your browser, not ours.
Get started

Pick a tool. Get an answer. Understand it.

Free calculators get you the number. Pro turns it into a plan.