Download berechnen
Download-Dauer
| Dauer | — |
|---|---|
| Dateigröße | — |
| Bandbreite | — |
🔢 Dateigrößen im Kopf? Dann Zahlensysteme konvertieren.
Dateigröße + Bandbreite → exakte Download-Dauer.
| Dauer | — |
|---|---|
| Dateigröße | — |
| Bandbreite | — |
🔢 Dateigrößen im Kopf? Dann Zahlensysteme konvertieren.
The formula is simple: Duration = File Size ÷ Bandwidth.
Supports all common units from KB to TB as well as KiB, MiB, GiB.
The theoretical download duration: Duration (s) = File Size (bits) ÷ Bandwidth (bps). 1 GB (8 billion bits) at 100 Mbps = 80 seconds. In practice: +5–15% for TCP/IP overhead, latency, and server throttling.
Mbps ≠ MB/s! 1 Byte = 8 bits. 100 Mbps = 12.5 MB/s. Our calculator handles both — choose Mbps for your internet plan or MB/s for real transfer rates.
1 GB = 1,000,000,000 bytes (decimal), but 1 GiB = 1,073,741,824 bytes (binary). Your file manager usually shows GiB but labels it "GB". Choose GiB for file manager values, GB for provider specifications.
Steam Download (50 GB): 100 Mbps ≈ 1 hr 7 min. Gigabit ≈ 6 min 40 sec.
Netflix 4K (8 GB): 50 Mbps ≈ 21 min.
Windows ISO (6 GiB): DSL 16000 ≈ 53 min.
Three scenarios everyone knows: You want to install a 50 GiB Steam game and want to know whether the download finishes before the end of the workday. You plan to pull a large ISO overnight and want to estimate whether eight hours will cut it. Or you're wondering whether the pricier fiber plan is really worth it — comparing the advertised bandwidth with what your line actually delivers. For all three cases, the calculator gives you a solid number in a few seconds.
Enter the file size — for example 25 GiB for a game update. Pick the matching unit; GiB fits when the number comes from your file manager.
Choose the bandwidth: Mbit/s if you know your plan (100 Mbit/s), or MB/s if you measured a real transfer rate from Steam & co.
Read the result. Behind it is the formula Duration = File Size ÷ Bandwidth — the calculator does the unit conversion for you.
25 GiB at 100 Mbit/s: 25 GiB is about 214.7 billion bits, so at 100 Mbit/s that's roughly 2,147 seconds — just under 36 minutes. With a 250 Mbit/s line the time halves to about 14 minutes. Try it: the calculator gives you the same values without the mental math.
The biggest mix-up in everyday networking: a bit is not a byte. 1 Byte = 8 bits. Your plan is quoted in bits per second, downloads are measured in bytes per second — that's why Steam shows only 12.5 MB/s on a 100 Mbit/s line. Not a scam, just unit conversion. Confuse bits and bytes and you overestimate your speed by a factor of 8.
The calculator gives you the theoretical value — reality is usually 20–30% below it. Reasons: servers that throttle connections, Wi-Fi overhead from interference, and other people using the connection. Rule of thumb: expect 70–80% of the advertised speed. 100 Mbit/s becomes a realistic 70–80 Mbit/s — 12.5 MB/s becomes about 9–10 MB/s of actual transfer rate.
50 MB/s — by a factor of 8. 50 MB/s equals 400 Mbit/s. Never compare the bare number without checking the unit.
Because operating systems count in binary: 1 GiB = 1,073,741,824 bytes. Disk manufacturers count decimal (1 GB = 1,000,000,000 bytes) — hence the famous “missing” gigabytes.
Yes, both systems. You can choose between GB/MB/KB (decimal) and GiB/MiB/KiB (binary) — handy when comparing file manager values with plan specs.
Mbit (megabit) measures data rates, MByte (megabyte) measures storage sizes. 1 Byte = 8 bits — 100 Mbit/s becomes 12.5 MB/s.
More on the topic in our blog: Download-Zeiten kalkulieren. Unit conversion? The number converter helps. The IEC units KiB/MiB/GiB are defined in standard IEC 80000-13.