Transfer time

How Long Does It Take to Upload 100 GB at 10 Mbps?

Uploading or downloading a 100 GB file at 10 Mbps takes about 22 hours 13 minutes, assuming the full speed is sustained.

By the HeftySend team Last updated 8 October 2026 Free, no sign-up

Upload or download time

22 h 13 min

10 Mbps is 1.25 MB/s. 100 GB is 100,000 MB, and 100,000 ÷ 1.25 = 80,000 seconds.

With 10% protocol overhead: about 1 day. Assumes the speed holds for the whole transfer.

Calculate your own

Different file size, a speed in MB/s or Gbps, or the 10% overhead switched on? The calculator opens pre-filled with 100 GB and 10 Mbps; change either value and the answer and both reference tables update.

Open the calculator: 100 GB at 10 Mbps

Works without JavaScript; the result is in the page when it loads.

What 100 GB actually is

One hundred gigabytes is about four hours of 4K footage, a full laptop user profile, a sizeable video-editing project with its proxies and renders, or a complete photo archive for a year. It is the largest transfer HeftySend accepts free with no account, so it is a natural reference point.

A 100 GB transfer is an overnight job on most home upload links and a lunchtime job on fibre. Because it spans hours, assume the connection will drop at least once and plan for it: a transfer that resumes from the last confirmed part finishes; one that does not may never finish on a flaky link.

4K video (55 Mbps): about 4 hours
1080p video (15 Mbps): about 15 hours
RAW photos (40 MB each): about 2,500
25 MB email attachments: about 4,000

What 10 Mbps actually is

10 Mbps is what the upload side of many cable and FTTC/VDSL plans actually delivers, a typical 4G upload indoors, and about the download speed of a good ADSL2+ line. It moves 1.25 MB of file data a second, so a megabyte takes a little under a second and a gigabyte a little over thirteen minutes.

Is 10 Mbps a realistic upload speed? As an upload speed it is realistic, even common: run a speed test on a plan sold as "100 Mbps" cable and 10 Mbps up is a normal result. As a download speed it is slow by today's standards; if that is all you measure, you are on ADSL, a congested mobile cell or Wi-Fi at the edge of its range.

100 GB at other speeds, and other sizes at 10 Mbps

The first table keeps the file at 100 GB and changes the speed; the second keeps the speed at 10 Mbps and changes the file. Rows with their own write-up are linked. Every row is also written out as a sentence under "In words".

100 GB at neighbouring connection speeds
Connection speed	Time for 100 GB
10 Mbps	22 h 13 min
25 Mbps	8 h 53 min
50 Mbps	4 h 26 min
100 Mbps	2 h 13 min
500 Mbps	26 min 40 s

In words

100 GB at 10 Mbps takes about 22 hours 13 minutes.
100 GB at 25 Mbps takes about 8 hours 53 minutes.
100 GB at 50 Mbps takes about 4 hours 26 minutes.
100 GB at 100 Mbps takes about 2 hours 13 minutes.
100 GB at 500 Mbps takes about 26 minutes 40 seconds.

Neighbouring file sizes at 10 Mbps
File size	Time at 10 Mbps
10 GB	2 h 13 min
20 GB	4 h 26 min
50 GB	11 h 6 min
100 GB	22 h 13 min
1 TB	9 d 6 h

In words

10 GB at 10 Mbps takes about 2 hours 13 minutes.
20 GB at 10 Mbps takes about 4 hours 26 minutes.
50 GB at 10 Mbps takes about 11 hours 6 minutes.
100 GB at 10 Mbps takes about 22 hours 13 minutes.
1 TB at 10 Mbps takes about 9 days 6 hours.

Why it usually takes longer than 22 hours 13 minutes

Protocol overhead

The headline figure assumes every bit of the 10 Mbps carries file data. In practice TCP/IP headers, TLS and HTTP framing take 5–10% of the link, so a more realistic estimate for 100 GB at 10 Mbps is about 1 day with 10% overhead, 2 hours 13 minutes longer. Quote that figure when someone is waiting for the file.

Upload is not download

The formula gives the same 22 hours 13 minutes for an upload and a download, but the speed you should plug in is rarely the same. 10 Mbps is usually the download speed of a plan; on an asymmetric cable, 4G or satellite link the upload side of that plan is often around 1 Mbps, which turns 22 hours 13 minutes into about 9 days 6 hours for the same 100 GB. When you are the one sending, run a speed test and use the upload number.

Dropped connections

Over 22 hours 13 minutes something can interrupt the transfer: a Wi-Fi roam, a laptop lid, a mobile hand-off between masts. A plain browser upload starts again from zero; a transfer that uploads in parts and resumes from the last confirmed part loses seconds. HeftySend uploads are resumable by default; the single button below takes you to the uploader.

Sending something big? Let it survive a dropped connection.

HeftySend uploads in parts and resumes from the last confirmed part, so a Wi-Fi blip or a sleeping laptop costs seconds, not the whole transfer. No account needed for transfers up to 100 GB.

Send up to 100 GB free

Frequently asked questions

How long does it take to download 100 GB at 10 Mbps?

About 22 hours 13 minutes, the same as uploading, because the formula is file size divided by speed in both directions. The practical difference is that 10 Mbps is far more likely to be a real download speed than a real upload speed: plans advertise the download figure, and on cable, 4G and satellite the upload side is a fraction of it. If you are downloading 100 GB on a 10 Mbps plan, this estimate is usually close; if you are uploading, measure your upload speed first.

How long does 100 GB take at 10 Mbps with protocol overhead?

About 1 day once you allow 10% for TCP/IP headers, TLS and HTTP framing, which is 2 hours 13 minutes longer than the raw 22 hours 13 minutes. Real transfers lose 5–10% of the link rate to that framing, so the overhead figure is the better one to quote when someone asks when 100 GB will arrive.

What if my connection only manages half of 10 Mbps while sending 100 GB?

Transfer time scales directly with speed: at 5 Mbps the same 100 GB takes about 1 day 20 hours, and at 2.5 Mbps about 3 days 16 hours. Wi-Fi, other devices on the network, a busy receiving server or a laptop on battery can each take a connection well below its headline figure, so a speed test taken right before you send is the only reliable input.

How many megabytes per second is 10 Mbps, and how does that give 22 hours 13 minutes for 100 GB?

10 Mbps is 1.25 MB/s, because there are 8 bits in a byte. 100 GB is 100,000 MB, and 100,000 ÷ 1.25 = 80,000 seconds, which is 22 hours 13 minutes. The calculator uses decimal units (1 GB = 1,000 MB); a file that Windows reports as 100 GB is about 7% larger in decimal terms and takes correspondingly longer.