Download Time Calculator
Estimated download time from file size and connection speed.
Enter your values
Enter the file size in GB.
Enter the connection speed in Mbps.
Enter the real-world efficiency in %.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Estimated time
- 8.9 minutes
- Estimated time
- 537 seconds
- Effective throughput
- 80 Mbps
Quick answer
Time = file size (in bits) / connection speed (in bits per second).
t = size / speed
At a glance
| What it does | Estimated download time from file size and connection speed. |
|---|---|
| Category | Technology |
| Inputs needed | File size, Connection speed, Real-world efficiency |
| Main output | Estimated time |
| Formula | t = size / speed |
| Cost | Free — no sign-up, no download |
How to use the Download Time Calculator
- 1Enter the file size in gigabytes.
- 2Enter your connection's rated speed in megabits per second (Mbps, not MB/s).
- 3Apply a real-world efficiency factor since actual throughput is usually below the rated speed.
Inputs explained
- File size(GB)
- Enter the file size in GB.
- Connection speed(Mbps)
- Enter the connection speed in Mbps.
- Real-world efficiency(%)
- Enter the real-world efficiency in %.
Worked example
Using the values the calculator loads with:
Inputs
- File size5 GB
- Connection speed100 Mbps
- Real-world efficiency80 %
Results
- Estimated time8.9 minutes
- Estimated time537 seconds
- Effective throughput80 Mbps
Frequently asked questions
Why is my download slower than my plan speed?
Rated speed is in megabits, not megabytes, and overhead, Wi-Fi and server limits also reduce real throughput.
How do I convert Mbps to MB/s?
Divide by 8: a 100 Mbps connection can theoretically reach about 12.5 MB/s.
What do I need to enter into the Download Time Calculator?
Just 3 values: file size, connection speed, real-world efficiency. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Download Time Calculator work out the answer?
Time = file size (in bits) / connection speed (in bits per second). It applies the formula t = size / speed and shows the working so you can check each step by hand.
Is the Download Time Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.