Reading Gigabit Numbers on a Wi-Fi or Ethernet Box
Shopping for an access point or a switch means staring at gigabit figures: 5.4 Gb on the front of a Wi-Fi 6 carton, 2.5 Gb beside a switch port, 10 Gb on an uplink module. None of them say how big a folder you can push across the link, because networking counts bits while your file manager counts bytes.
5.4 Gb becomes 5.4 ÷ 8 = 0.675 GB. Hold that rate for a minute and the link has carried 0.675 × 60 = 40.5 GB.The Lower-Case b Carries the Meaning
Vendors Add the Radios Together
Duplex Counts Each Direction
Turning a Spec-Sheet Rate Into a File-Copy Estimate
Type the Headline Figure
Enter the gigabit number as printed — 2.5, 4.804, 5.4, 10. Comma or dot both work as the decimal mark and spaces are ignored, so a figure pasted from a datasheet still parses.
Read the Gigabyte Side
The result updates as you type. Read it as gigabytes per second, then multiply by 60 for a per-minute figure or by 3 600 for an hour.
Copy the Bare Number
The copy button on each field hands over the digits alone, with no unit — useful when you are filling a comparison sheet for two or three access points.
Change Units When the Sheet Does
Both sides carry a searchable dropdown of every data unit, so a sheet quoting megabits or a throughput test reporting MB/s is handled on the same page.
Going the other way: the swap button reverses the direction and both fields stay editable. Type the sustained gigabytes per second you measured in a real copy into the right-hand field to read back the gigabits it corresponds to — the honest number to hold against the vendor's claim.
Link Speeds and the Data They Actually Move
Every rate below is a PHY rate: the signalling speed the radio or the copper negotiates, before framing, headers, retries and channel contention take their cut. The final column is a ceiling.
| Link as printed on the spec sheet | Gigabits | Gigabytes per second | Ceiling per minute |
|---|---|---|---|
| Wi-Fi 6, 2.4 GHz radio, 2×2 | 0.574 Gb | 0.07175 GB | 4.3 GB |
| Gigabit Ethernet (1000BASE-T) | 1 Gb | 0.125 GB | 7.5 GB |
| Wi-Fi 6, 2×2 on a 160 MHz channel | 2.4 Gb | 0.3 GB | 18 GB |
| 2.5GBASE-T switch port | 2.5 Gb | 0.3125 GB | 18.75 GB |
| Wi-Fi 6, 5 GHz radio, 4×4 at 160 MHz | 4.804 Gb | 0.6005 GB | 36.03 GB |
| "AX5400" combined box rating | 5.4 Gb | 0.675 GB | 40.5 GB |
| 10GBASE-T port | 10 Gb | 1.25 GB | 75 GB |
Wired links land close to that ceiling: a healthy gigabit LAN sustains roughly 110–118 MB/s on a large copy, about 6.6–7.1 GB per minute against a theoretical 7.5. Wi-Fi is far less generous, commonly settling between a third and a half of the negotiated PHY rate — which is why the 40.5 GB per minute implied by a 5.4 Gb carton is a figure no household sees.
Check the Vendor's Arithmetic Both Ways
Enter the GB/s a review measured and swap the direction to see what gigabit rating the hardware would need to justify it.
Per-Band and Combined Ratings Side by Side
Run the 5 GHz figure, then the marketing total. Two conversions show how much of the box number belongs to a radio you rarely join.
Megabit Sheets Handled Too
Older access points list 574 Mb or 1 201 Mb. Pick the megabit unit in the dropdown instead of dividing by a thousand first.
Numbers Ready for a Shortlist
Copy either field to get the value with no unit and no thousands spacing, so candidate switches line up cleanly in a spreadsheet column.
Wi-Fi and Ethernet Spec Questions
Why does the router box say 5.4 Gb when no device gets close to it?
That figure sums every radio at its best-case modulation — 4 804 Mb on 5 GHz plus 574 Mb on 2.4 GHz. A client joins one band with only as many spatial streams as its own antennas support, so a two-stream laptop is really shopping in the 2.4 Gb column: 0.3 GB per second of ceiling, not 0.675.
What separates a PHY rate from the throughput I can measure?
The PHY rate is how fast symbols travel once a frame is being transmitted. Throughput is what survives preambles, acknowledgements, TCP and IP headers, retries and waiting for a free channel. On Wi-Fi that overhead routinely removes half the headline; on switched Ethernet it removes a few percent.
My LAN is gigabit, so why does a large copy sit at 110 MB/s?
Because 110 MB/s is what a gigabit link looks like when it is working properly. The 1 Gb rate converts to 0.125 GB/s — 125 MB/s of raw signalling — and Ethernet framing plus per-packet headers consume the difference. Anything in the 110–118 MB/s band means cable, switch and both network cards are fine.
Do I have to rewire the house for a 2.5 Gb or 10 Gb port?
2.5GBASE-T was designed to run over the Cat 5e already in most walls at ordinary room-to-room lengths, so the jump from 0.125 to 0.3125 GB/s usually costs only the switch. 10GBASE-T is stricter: Cat 6 manages shorter runs and a full 100 m link wants Cat 6a. Read the print on the cable jacket first.
Does full duplex mean I should double the gigabit figure?
Not for a single transfer. Full duplex lets the port carry its rated gigabits in each direction at once, which is why a switch datasheet may advertise 2 Gb of aggregate capacity per gigabit port. Pulling a folder off a NAS uses one direction, so the conversion that matters stays 1 Gb to 0.125 GB per second.
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