No. 01 · Noon
Every formula, shown.
The formula, then a worked example with your numbers in it. Each variable and assumption is documented.
Worked example
h = s × tan θ
h = 2.77 m × tan 77° = 12.0 m
Calculators for finance, science, health and everyday life, with the working shown.
269+ free calculators
From basic math to complex scientific calculations, financial planning to health metrics — find the perfect calculator for every need.
⌘K to search from anywhere
No account. No ads. Runs in your browser.
Fig. 1 — Sun at 35°: the shadow measures 17.14 m, so h = s × tan θ = 17.14 m × tan 35° = 12.0 m. Open the Triangle calculator →
Every calculator page shows the formula, plus a worked example with your inputs substituted. Each variable and assumption is documented. No black-box math.
Change a number ↘
Triangle · height from a shadowNoon on the terrace
h = s × tan θ
Fig. 2 — The same triangle as the plate above. Change the shadow or the angle and the obelisk follows.
No. 01 · Noon
The formula, then a worked example with your numbers in it. Each variable and assumption is documented.
Worked example
h = s × tan θ
h = 2.77 m × tan 77° = 12.0 m
No. 02 · Afternoon
Calculations never reach a server. No accounts, no email list, no third-party trackers.
Network
| Name | Status | Size |
|---|---|---|
| — |
0 requests · 0 B transferred
No. 03 · Golden hour
Built on math.js. Formulas come from textbooks and primary references, and each calculator documents its source and assumptions.
Source & assumptions
No. 04 · Dusk
Copy the URL and opening it restores your inputs. Embed any calculator at /embed/[calculator-slug].
Share
Embed: /embed/triangle-calculator
Most-used tools by our community
Find calculators organized by topic
Common questions about how Ekuation works, what it costs, and what to expect.
A free online calculator catalog. Over 90 calculators across 19 categories — finance, science, health, math, conversions, everyday tasks. Every calculator shows the formula and a worked example. No account, no paywall, no ads.
Different priorities. Omnicalculator covers breadth (5,000+ tools). Ekuation focuses on showing the formula behind each calculator and explaining the math. Ekuation also runs no ads, requires no signup, and supports German.
Yes. No account, no payment, no ads, no premium tier, no upsell. Every calculator works without restriction. Use any of them as much as you want.
No. Click any calculator, enter your inputs, get the result. No signup, login, or email field. Bookmark a calculator and come back whenever — the URL works without authentication.
19 categories: math, finance, science, health, food, music, sports, time, and everyday-life tasks. Each category groups calculators with their formulas and step-by-step worked examples. Browse them on the homepage.
We're constantly adding new calculators. Let us know what you need and we'll build it.
Fig. 8 — Night. No sun, no shadow, no triangle. The lighthouse keeps the harbour until morning.
Search and find calculators