ferro·web

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Try one of these:

Tip: tap ƒx for the reference, a/b for exact fractions & surds, and the rail icons to open panels (drag a panel to pin it left or right).

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angles in {{preview.angleHint}}

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Enter an expression…{{tok.text}}

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Reference

Variables & functions

Assign with r = 50 or define f(x) = x^2. They appear here.

Programmer

a copy — ans untouched

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Bits

⚠{{progTruncMsg}}

Apply to value

evaluate an integer and its bits appear here

Like this? You’ll love the fully-featured offline desktop app — faster, and works with no internet.

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Online engineering & scientific calculator

ferro is a free, browser-based engineering and scientific calculator built for electronics, RF, and embedded engineers. Type expressions naturally and get instant results in engineering or SI notation — kilo, mega, milli, micro, nano, pico — with exact arbitrary-precision arithmetic, so there is no floating-point drift.

What it does

Engineering & SI notation, plus decimal, hexadecimal, octal and binary output
Exact rational fractions — 1/3 stays 1/3, and 0.1 + 0.2 is exactly 0.3
Complex numbers, decibels (dB / dBm) and physics constants
A programmer mode with an interactive bit grid and 8 / 16 / 32 / 64-bit words
Runs entirely in your browser — fast, private, and works offline once loaded

Shortcuts & syntax

Keyboard

Syntax

What's new

v{{c.v}} · {{c.d}}

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Runs entirely in your browser — nothing leaves your device. v{{version}}

click any line to copy

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