Download-time calculator
Estimate how long a download will take, from the file size and your connection's download speed.
Result
Estimated download time
How to use this tool
- Enter the file size — switch between MB and GB if needed. If your operating system labels a binary GiB value as GB, see the note below.
- Enter your download speed in Mbps (megabits per second) — check a speed test if you don't know it.
- Read the estimated download time.
Assumptions
- Assumes your full connection speed is available for the whole download, with no other traffic sharing it and no server-side bottleneck — real-world downloads are often slower than this ideal estimate.
- This input uses decimal MB/GB. Some operating systems display binary MiB/GiB but label them MB/GB; 1 GiB is about 1.074 decimal GB, so using that displayed value without conversion can understate the time.
Sources & reference data
Technical details: what the fields mean
- File size
fileSize - Size of the file or content being downloaded.
- Download speed
speedMbps - Your connection's download speed in Mbps — note this is megabits, not megabytes, per second.
Methodology
Time (seconds) = file size (megabits) ÷ speed (Mbps). File size uses decimal MB/GB (1 GB = 1000 MB) and is converted to megabits by multiplying by 8, since 1 byte = 8 bits.
Worked example
Illustrative 5,000 MB file at 100 Mbps
Inputs: File size: 5000 mb, Download speed: 100 Mbps
Result: 5000 MB × 8 = 40,000 megabits; ÷ 100 Mbps = 400 seconds, or 6.7 minutes before network overhead.
Practical guidance
- For a more realistic input, run a speed test on the same device, connection and location you plan to download from; Wi-Fi signal and network congestion vary over time.
- If the source server limits your download rate, the actual transfer will be slower even when your connection has spare capacity.
Common mistakes
- Confusing Mbps (megabits per second, how speed is advertised) with MB/s (megabytes per second, how file sizes and progress bars are usually shown) — divide Mbps by 8 to get MB/s.
FAQs
My computer shows a 1 GiB file. What size should I enter?
Enter about 1.074 decimal GB, or 1,073.74 MB. A GiB is 1,073,741,824 bytes, while this calculator uses decimal GB (1,000,000,000 bytes).
Last reviewed: 2026-10-11
This is a best-case transfer estimate, not a completion-time guarantee; throughput can vary during a download.
This tool provides an indicative estimate, based on the assumptions stated above.
Theme and tool preferences, along with saved and recently used lists, are stored only in this browser.