Transferring 100 GB over Gigabit Ethernet takes 13m 20s

A 100 GB transfer over Gigabit Ethernet works out to 13 minutes 20 seconds at the full 1000 Mbps peak. That's the typical figure you'll see on a well-tuned home LAN — modern NICs, a proper switch, and a fast disk at both ends. SMB and NFS add single-digit percentage overhead once the link is warm.

Transfer time
13m 20s
At peak link speed
File size
100 GB
100 GB
Link speed
1,000 Mbps
Gigabit Ethernet (1000 Mbps)

Calculator

Data Transfer Calculator

Configuration

Mbps
Estimated Transfer Time
13m 20s

Speed Comparison

USB 2.0
27m 46s
480 Mbps
USB 4 / Thunderbolt 4
20s
40 Gbps
Gigabit Ethernet
13m 20s
1 Gbps
Selected
10 Gigabit Ethernet
1m 20s
10 Gbps
WiFi 5 (ac)
33m 20s
400 Mbps
WiFi 7 (be)
2m 40s
5 Gbps
SATA SSD
3m 1s
4.4 Gbps
NVMe Gen4 SSD
14s
56 Gbps

How this is calculated

Real-world Gigabit sustained throughput lands around 110–115 MB/s, which stretches the transfer to about 14–15 minutes. WiFi on a 5 GHz 80 MHz channel usually hits 40–70% of this in practice despite advertised speeds. For a home NAS to saturate Gigabit, both source and destination disks need to beat ~120 MB/s sustained — which any recent NAS-class drive does easily.

Verdict

13m 20s for 100 GB is Gigabit Ethernet's practical floor. It's the baseline against which 2.5 GbE (5m 20s) and 10 GbE (1m 20s) upgrades should be measured when planning a home or small-office network.

More Ethernet scenarios

Frequently asked questions

How long does it take to transfer 1 TB over Gigabit Ethernet?
At a theoretical 1000 Mbps (125 MB/s), 1 TB takes about 2 hours and 13 minutes in ideal conditions. Real-world speeds over Gigabit Ethernet typically top out around 110-115 MB/s due to TCP overhead, so budget closer to 2.5 hours for a full 1 TB copy.
Why is my real transfer speed slower than the cable's rated speed?
Rated speeds are raw signalling rates in bits per second. Protocol overhead (TCP/IP, USB framing, filesystem operations), encryption, small-file latency, and the slowest device in the chain (often the disk, not the cable) all reduce usable throughput. A USB 3.0 port rated 5 Gbps usually delivers around 400 MB/s in practice, not the theoretical 625 MB/s.
What's the difference between megabits (Mbps) and megabytes (MB/s)?
There are 8 bits in a byte, so 1000 Mbps equals 125 MB/s. Network speeds and ISP plans are advertised in megabits per second, while file sizes and storage speeds are measured in megabytes per second. Dividing Mbps by 8 gives you the MB/s figure you actually see when copying files.
How fast is WiFi 6 compared to Gigabit Ethernet for file transfers?
WiFi 6 can exceed Gigabit Ethernet on paper (up to ~9.6 Gbps theoretical) but real-world throughput usually lands between 500 Mbps and 1.5 Gbps depending on distance, interference, and client hardware. For a single large file transfer, wired Gigabit is still more consistent; WiFi 6E or WiFi 7 can edge ahead in ideal conditions.
Is USB 4 or Thunderbolt 4 faster for copying files?
Both use the same 40 Gbps underlying spec and deliver comparable real-world speeds of around 2800-3200 MB/s for sustained transfers. Thunderbolt 4 guarantees the full 40 Gbps and PCIe 32 Gbps tunnel; USB 4 allows 20 Gbps implementations, so check the port's actual spec rather than assuming parity.
Does file size affect transfer speed?
Yes — significantly. Transferring one 50 GB file hits near-maximum throughput, but copying 50 GB of small files (thousands of photos, say) can be 5-10x slower because every file has filesystem and metadata overhead. For large migrations, compressing into an archive first is often faster end to end.