“300 megabits per second” sounds like 300 megabytes of Netflix will land on your laptop every second. It won’t. Here is the short course in plain English.

1. The Math in One Line  

300 megabits per second (Mb/s) ÷ 8 = 37.5 megabytes per second (MB/s).  

After normal network overhead you’ll actually see about 32 MB/s—still enough for four 4K streams or one furious Steam download.

2. Bits vs. Bytes  

Providers advertise in bits (little b). Your computer measures in Bytes (big B).  

8 bits = 1 Byte.  

1 Mb/s = 128 KB/s.  

Remember the eight and you’ll never be fooled again.

3. Download ≠ Upload  

A plan sold as “300 Mb/s” usually means 300 down, 30 up. So:  

House A: 10 MB/s download  

House B: 10 MB/s upload  

House A’s pipe is roughly ten times fatter. If you Zoom, live-stream, or back-up photos to the cloud, check the upstream number before you sign.

4. Which Speed Tier Fits?  

100 Mb/s (12 MB/s) – 1–2 people, web, SD video.  

300 Mb/s (37 MB/s) – 2–3 people, HD video, casual gaming.  

500 Mb/s (62 MB/s) – 4–5 people, 4K HDR, competitive gamers.  

1000 Mb/s (125 MB/s) – multi-device 4K, cloud work, smart-home heaven.

5. The Fine Print  

Your measured speed is only as good as the slowest link: optical modem, router, Ethernet cable (Cat 5e or better), even the phone in your hand. Upgrade those first before you blame the line.

Bottom line: 300 Mb/s is already “plenty fast” for most homes. Learn the eight-bit rule, glance at the upload column, and you’ll buy exactly the bandwidth you need—no more, no less.