Download Time Calculator

Calculate how long a download will take, given the file size and your connection speed.

  • Free to use
  • Accurate results
  • No registration required
  • Works on all devices
Download time = file size (in bits) ÷ connection speed (in bits per second). Enter your file size and speed to calculate it.

Your result

6m 40s

Download time

Download time (seconds)400 seconds

AI explanation

Formula

Download time = (file size in bits) ÷ (connection speed in bits per second)

Worked example

5GB file at 100 Mbps

Worked example: 5GB file at 100 Mbps
FieldValue
File size5
File size unitGB
Connection speed100
Speed unitMbps
Download time6m 40s
Download time (seconds)400

Assumptions

  • Uses decimal (SI) units throughout — 1 MB = 1,000,000 bytes, 1 Gbps = 1,000 Mbps — matching how ISPs advertise speeds.
  • Assumes the full advertised speed is sustained for the entire download with no interruptions or competing traffic — real-world downloads are usually slower.

Frequently asked questions

Why is my actual download slower than this calculation?

Real connections rarely sustain their full advertised speed due to network overhead, other devices sharing the connection, server-side limits, and Wi-Fi signal quality — this calculator shows the theoretical best case.

Why is the unit Mbps and not MB/s?

Internet speeds are conventionally advertised in megabits per second (Mbps), while file sizes are shown in megabytes (MB) — there are 8 bits per byte, so this matters for accurate time estimates.

Can I use this for streaming instead of downloading?

This estimates a full-file download time — for streaming, what matters is whether your speed exceeds the stream's bitrate, not the total file size.

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