Bit vs Byte: What's the Difference?
Bits and bytes are the two fundamental units of digital data — and confusing them is the number one reason people think their internet is slow. Here's the simple explanation.
The Core Difference
A bit is the smallest unit of data. It can only be 0 or 1. A byte is a group of 8 bits. That's it. 8 bits = 1 byte. This single fact explains almost every confusing number you see in tech.
Why This Matters for Internet Speed
Your internet provider advertises speed in Mbps — Megabits per second. Your download manager shows speed in MB/s — Megabytes per second. Because 1 byte = 8 bits, your MB/s speed will always be 8 times lower than your Mbps speed.
Example: 100 Mbps connection ÷ 8 = 12.5 MB/s actual download speed. Your internet is not lying to you — you're just comparing bits to bytes.
Bits vs Bytes at a Glance
Bits (lowercase b) — used for network speeds: Kbps, Mbps, Gbps
Bytes (uppercase B) — used for file sizes and storage: KB, MB, GB, TB
The Metric Prefixes
Both bits and bytes use the same prefixes, which makes things more confusing:
- Kilo = 1,000 (or 1,024 in binary)
- Mega = 1,000,000
- Giga = 1,000,000,000
- Tera = 1,000,000,000,000
So 1 Megabit = 1,000,000 bits. 1 Megabyte = 8,000,000 bits. Always 8x apart.
Frequently Asked Questions
What is the difference between a bit and a byte?
A bit is the smallest unit of data (0 or 1). A byte is 8 bits. File sizes are measured in bytes (KB, MB, GB) while internet speeds are measured in bits per second (Mbps, Gbps).
Why does my 100 Mbps internet only download at 12 MB/s?
Because internet speed is measured in Megabits (Mb) and your download speed shows Megabytes (MB). Since 1 byte = 8 bits, divide your Mbps by 8 to get your MB/s speed: 100 ÷ 8 = 12.5 MB/s.
Is Mbps bits or bytes?
Mbps is Megabits per second — it uses bits. The lowercase 'b' in Mbps stands for bits. Uppercase MB means Megabytes (bytes). Always check the capitalisation.
How many bits are in a GB?
1 GB (Gigabyte) = 8 Gigabits = 8,000 Megabits = 8,000,000,000 bits. Or using binary: 1 GB = 8,589,934,592 bits.
Which is bigger, a bit or a byte?
A byte is bigger. 1 byte = 8 bits. So a Megabyte (MB) is 8 times larger than a Megabit (Mb).