Live Binary Clock

Watch the current time expressed in binary, updating live every second. Switch between 12-hour and 24-hour format and see exactly how each digit maps to its binary bits.

Binary Clock
00:00:00 AM
Hours
8
4
2
1
0
0
0
0
0
0
0
0
Minutes
8
4
2
1
0
0
0
0
0
0
0
0
Seconds
8
4
2
1
0
0
0
0
0
0
0
0
Each row of 4 bits represents one decimal digit — add up the highlighted values to read it.

How to Read a Binary Clock

This binary clock displays time using binary digits (bits). Each time unit — hours, minutes, and seconds — is shown as two rows of 4 bits: one row for the tens digit, one for the ones digit.

Each bit represents a power of two: 8 4 2 1

To read the time, add up the values of every highlighted (green) bit in each row.

Time UnitTens Row RangeOnes Row RangeExample
Hours0–10–912 = 1 (tens) + 2 (ones)
Minutes0–50–937 = 3 (tens) + 7 (ones)
Seconds0–50–959 = 5 (tens) + 9 (ones)

What Is a Binary Clock?

A binary clock tells time using binary digits — 0s and 1s — instead of the familiar decimal numbers on a normal clock face. Rather than showing “14:35:22,” it represents each digit of the time as a small grid of lights, where a lit bit means “1” and an unlit bit means “0.”

The version above uses the Binary-Coded Decimal (BCD) format, which is the most common approach and the easiest to learn:

  • Hours, minutes, and seconds are each split into two digits — a tens digit and a ones digit.
  • Each digit gets its own row of 4 bits, representing the values 8, 4, 2, and 1 (powers of two, read left to right).
  • To read a digit, add up the values of every lit bit in its row.
  • Combine the tens and ones digit to get the full number for that unit — repeat for hours, minutes, and seconds to read the complete time.

How to Read the Binary Clock?

Once you know what each bit represents, reading it becomes second nature.

  1. Look at one row at a time. Each row corresponds to either a tens digit or a ones digit for hours, minutes, or seconds.
  2. Add up the lit bits. Every lit bit contributes its value (8, 4, 2, or 1) to the total. An unlit bit contributes nothing.
  3. Combine tens and ones. If the hours-tens row shows 1 lit (value 1) and the hours-ones row shows 2 lit (value 2), the hour is 12.
  4. Repeat for minutes and seconds. The same logic applies to every unit — just add the lit values in each row.

For example: if the minutes-tens row lights up 2 and 1 (2 + 1 = 3), and the minutes-ones row lights up 4 and 2 and 1 (4 + 2 + 1 = 7), the minutes read as 37.

It takes a little practice at first, but most people can read a binary clock at a glance within a few minutes of use.

What Is Binary Time?

“Binary time” simply means representing the current time using the binary numeral system — the same 0s and 1s that computers use internally — instead of the decimal digits we normally read. There are two common approaches:

  • BCD (Binary-Coded Decimal) — the format used by this clock and by most binary clocks and watches. Each individual decimal digit (0–9) is converted to its own 4-bit binary value and displayed separately.
  • True binary — a less common approach where the entire hour, minute, or total seconds-since-midnight is converted into one large binary number, rather than digit by digit.

BCD is more common because it’s easier to read at a glance — you’re decoding small, familiar 4-bit chunks rather than one long binary string.

Frequently Asked Questions

It’s not really a practical timekeeping tool — you won’t glance at it the way you would a normal clock. It’s primarily educational: a hands-on way to understand how binary numbers work and how computers represent data internally, with a bit of retro-tech charm built in.

Yes. Physical binary watches and desk clocks are sold by various retailers, including on marketplaces like Amazon, eBay, and AliExpress, for anyone who wants binary timekeeping on their wrist rather than just on screen.

A typical hardware binary clock is built from LED lights arranged in a grid, a microcontroller to run the timekeeping logic, a power supply, resistors to protect the LEDs, and pushbuttons for setting the time.

Each row of 4 bits represents one decimal digit, with bit values of 8, 4, 2, and 1 from left to right. Add up the values of the lit bits in a row to get that digit, then combine the tens-digit and ones-digit for each unit (hours, minutes, seconds) to read the full time — for example, a lit 8 and 1 in one row and a lit 2 in the next gives you 9 and 2, or “92” read together (in practice capped appropriately, e.g. hours never exceed 23 in 24-hour format).

No. Unix time counts seconds elapsed since January 1, 1970, and could theoretically be shown in binary too — but that’s a single continuously growing number, not a clock face. A binary clock like this one still shows the familiar hours, minutes, and seconds — just written in binary instead of decimal.

To convert your own binary values, visit the Binary Code Converter homepage.