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Ted's Converters

Numbers, codes, science & more

Number Converter

Computers store everything in binary (base 2). Convert any whole number to see how it looks in different bases.

Binary (base 2)
enter a number
Hexadecimal (base 16)
enter a number
Octal (base 8)
enter a number
Bits needed
enter a number

Text to Binary

Every character has an ASCII code. See what your name looks like when a computer stores it in binary!

Binary output
type something above

Morse Code

Dots (·) and dashes (—) used by ships and telegraphs since the 1800s. Spaces become /

Morse code
type something above

Roman Numerals

Used in film credits, clocks, Super Bowls and history books. I=1, V=5, X=10, L=50, C=100, D=500, M=1000.

Roman numerals
enter a number

Caesar Cipher

Julius Caesar shifted each letter by 3 to send secret messages to his generals. Drag the slider to choose your own shift!

3
Encoded (shifted forward)
type a message above
Decoded (shifted back)
type a message above

Temperature Converter

Science uses Celsius and Kelvin; the USA uses Fahrenheit. Absolute zero (0 K) is the coldest anything can ever be.

Celsius (°C)
—
Fahrenheit (°F)
—
Kelvin (K)
—
What's that like?
—

Metric & Imperial

The UK uses both! Science uses metric, road signs are in miles, and people still weigh themselves in stone.

Conversions
enter a value above

Colour Converter

Computers describe colours as three numbers: Red, Green, Blue (0–255). Click the wheel to pick a colour, or type a hex code.

#FF5733
Click to open colour wheel
Red
—
Green
—
Blue
—
CSS rgb()
—

Fractions

Every fraction can be written as a decimal or percentage. Enter the top (numerator) and bottom (denominator) numbers.

÷
Decimal
—
Percentage
—
Simplified fraction
—

pH Scale

pH measures how acidic or alkaline a liquid is. 0–6 acidic · 7 neutral · 8–14 alkaline. You'll use this in Year 7 science!

0 — Acid7 — Neutral14 — Alkali
Type
—
Nearest example
—
pHTypeExample

Times Tables

Pick a number to see its full times table up to ×20. Great for practising before secondary school!

Time Zones

Click or drag the red line across the map to pick a longitude. The world is divided into 24 main zones — the UK is UTC+0 in winter, UTC+1 in summer (BST).

UTC+0 — drag the red line!
Time at selected zone
—
UK time right now
—
Difference from UK
—
Cities in this zone
—

World clock (live)

Computer Memory

A bit is the smallest unit of data (0 or 1). Everything on a computer — photos, games, videos — is made of bits!

Conversions
enter a value above
Scale guide:
A text message ≈ 1 KB · A photo ≈ 3–5 MB · A song ≈ 5 MB · A film ≈ 4 GB · A large game ≈ 50–100 GB · 1 TB hard drive holds ≈ 250,000 photos

Ohm's Law

Fill in any two values and the third will be calculated automatically.

V = Voltage (Volts, V) — the "push" that drives electricity around a circuit
I = Current (Amps, A) — how much electricity is actually flowing
R = Resistance (Ohms, Ω) — how hard it is for electricity to flow

Push harder (↑V) → more flows. More resistance (↑R) → less flows.
V
I
R

Cover the letter you want: V = I × R · I = V ÷ R · R = V ÷ I

Result
fill in any two values above

Enigma Machine

The Enigma machine was used by Germany in WW2 to send secret messages. Each letter is scrambled through a rotor — and after every letter the rotor clicks one step forward, changing the scrambling!

How it works — 3 steps per letter:
1️⃣ Signal goes forward through the rotor (shifts by position, looks up the wire)
2️⃣ Signal hits the reflector — a fixed "mirror" that bounces it back
3️⃣ Signal goes back through the rotor (in reverse) → lamp lights up

The reflector is the clever bit: because every letter maps to a different letter and the pairing is mutual (if A↔X then X↔A), the whole machine is self-reciprocal. Type HELLO → get ADGRZ. Type ADGRZ → get HELLO back. No mode switch needed!

Reflector used here: UKW-B = YRUHQSLDPXNGOKMIEBFZCWVJAT
(e.g. A↔Y, B↔R, C↔U … all pairs are mutual)
Output (same settings encrypt & decrypt)
type a message above