# Bandwidth and download time calculator

> Download or upload time for a file at a given speed, the data a link moves in a set time, and a website's monthly bandwidth from page views.

ಸಂವಾದಾತ್ಮಕ ಆವೃತ್ತಿ: https://www.calcopenly.com/kn/programming/bandwidth-data-transfer-calculator
ವಿಷಯ: ಪ್ರೋಗ್ರಾಮಿಂಗ್ ಮತ್ತು ತಂತ್ರಜ್ಞಾನದ ಕ್ಯಾಲ್ಕುಲೇಟರ್‌ಗಳು

Transfer time is the size in bits divided by the speed in bits per second: t = 8 × bytes ÷ (rate × (1 − overhead)). The factor of 8 is there because internet plans quote megabits per second while files are measured in bytes. The other two modes run the same equation the other way, for the data a link moves in a set time, or multiply page views by page weight for a website's monthly traffic.

The default, a 50 GB download on a 100 Mbit/s plan with 5% protocol overhead, takes 1 h 10 min 10 s; with no overhead it would take 1 h 6 min 40 s. A site with 100,000 monthly views of a 2 MB page serves 200 GB a month.

Real downloads can be slower than the result when the server, Wi-Fi or a congested route caps the speed below the plan's rate. Sizes follow IEC 80000-13: 1 GB is 10^9 bytes and 1 GiB is 2^30 bytes.

## ಒಳಾಂಶಗಳು

- **ನಾನು ಕಂಡುಹಿಡಿಯಬೇಕಾಗಿರುವುದು** (ಆಯ್ಕೆಗಳು: Transfer time, Data moved in a time, Website monthly bandwidth)
- **Data size**
- **Connection speed**: Internet plans quote megabits per second (Mbit/s); download dialogs often show megabytes per second (MB/s), 8 times smaller.
- **Time spent transferring**
- **Protocol overhead**: Share of the line rate lost to packet headers. TCP/IPv4 over Ethernet carries 1460 payload bytes per 1538 bytes on the wire, about 5%.
- **Page views per month**
- **Average page weight**: Everything one view downloads (HTML, scripts, images). Your browser's network panel shows the total.
- **Days in the month**

## ಫಲಿತಾಂಶಗಳು

- Transfer time — ಮುಖ್ಯ ಫಲಿತಾಂಶ
- Transfer time in seconds (s)
- Data
- Data
- Payload speed after overhead (Mbit/s)
- Data per day (GB)
- Average speed needed (Mbit/s)

## ಸೂತ್ರ

$$
\begin{aligned} t &= \frac{8 \times \text{bytes}}{\text{rate} \times (1 - \text{overhead})} \\[4pt] \text{monthly} &= \text{views} \times \text{page weight}\end{aligned}
$$

## ಪರಿಹರಿಸಿದ ಉದಾಹರಣೆಗಳು

### 50 GB at 100 Mbit/s with no overhead

- ನಾನು ಕಂಡುಹಿಡಿಯಬೇಕಾಗಿರುವುದು: Transfer time
- Data size: 50 GB
- Connection speed: 100 Mbit/s
- Protocol overhead: 0%
- **Transfer time in seconds: 4,000 s**
- **Transfer time: 1 h 6 min 40 s**
- ಪರಿಶೀಲನೆಯ ಮೂಲ: Python 3.8: 50e9 × 8 / 100e6 = 4000 s

### Same transfer with 5% overhead

- ನಾನು ಕಂಡುಹಿಡಿಯಬೇಕಾಗಿರುವುದು: Transfer time
- Data size: 50 GB
- Connection speed: 100 Mbit/s
- Protocol overhead: 5%
- **Transfer time in seconds: 4,210.53 s**
- **Payload speed after overhead: 95 Mbit/s**
- ಪರಿಶೀಲನೆಯ ಮೂಲ: Python 3.8 decimal: 4000 / 0.95 = 4210.526315…

### 1 GiB at 1 Gbit/s (binary size, edge)

- ನಾನು ಕಂಡುಹಿಡಿಯಬೇಕಾಗಿರುವುದು: Transfer time
- Data size: 1 GiB
- Connection speed: 1 Gbit/s
- Protocol overhead: 0%
- **Transfer time in seconds: 8.59 s**
- ಪರಿಶೀಲನೆಯ ಮೂಲ: Python 3.8: 2**30 × 8 / 1e9 = 8.589934592 s

### One hour at 100 Mbit/s

- ನಾನು ಕಂಡುಹಿಡಿಯಬೇಕಾಗಿರುವುದು: Data moved in a time
- Connection speed: 100 Mbit/s
- Time spent transferring: 1 h
- Protocol overhead: 0%
- **Data: 45 GB**
- **Data: 41.91 GiB**
- ಪರಿಶೀಲನೆಯ ಮೂಲ: Python 3.8: 100e6 × 3600 / 8 = 45e9 B; 45e9 / 2**30 = 41.90951 GiB

### 100,000 views of a 2 MB page

- ನಾನು ಕಂಡುಹಿಡಿಯಬೇಕಾಗಿರುವುದು: Website monthly bandwidth
- Page views per month: 100,000
- Average page weight: 2 MB
- Days in the month: 30
- **Data: 200 GB per month**
- **Data per day: 6.667 GB**
- **Average speed needed: 0.617 Mbit/s**
- ಪರಿಶೀಲನೆಯ ಮೂಲ: Python 3.8 decimal: 1e5 × 2e6 = 2e11 B; 2e11 × 8 / (30 × 86400) = 617 283.95 bit/s

### Speed given in megabytes per second

- ನಾನು ಕಂಡುಹಿಡಿಯಬೇಕಾಗಿರುವುದು: Transfer time
- Data size: 700 MB
- Connection speed: 10 MB/s
- Protocol overhead: 0%
- **Transfer time in seconds: 70 s**
- **Payload speed after overhead: 80 Mbit/s**
- ಪರಿಶೀಲನೆಯ ಮೂಲ: Python 3.8: 700e6 / 10e6 = 70 s; 10 MB/s × 8 = 80 Mbit/s

## ಪ್ರಶ್ನೆಗಳು

### How long does it take to download 1 GB at 100 Mbps?

About 80 seconds at the full line rate: 1 GB is 8,000 megabits, and 8,000 ÷ 100 = 80 s. With 5% protocol overhead it takes about 84 s. At 10 Mbit/s the same file takes 13 min 20 s, and at 1 Gbit/s about 8 s, as long as the server and Wi-Fi keep up.

### What is the difference between Mbps and MB/s?

Mbps (megabits per second) measures network speed, while MB/s (megabytes per second) is how browsers and download managers show progress. One byte is 8 bits, so divide Mbps by 8: a 100 Mbit/s plan tops out at 12.5 MB/s, and 1 Gbit/s at 125 MB/s. Protocol overhead lowers the figure you see by a further few percent.

### Why is my download slower than my internet speed?

Part of the gap is protocol overhead: over Ethernet, TCP/IPv4 carries 1,460 bytes of data in each full 1,538-byte frame on the wire, so about 5% of the line rate goes to headers, preamble and inter-frame gap. The rest comes from the server's own limit, Wi-Fi signal, congestion on the route, or other devices sharing the connection.

### How much bandwidth does a website need per month?

Multiply monthly page views by the average page weight, which your browser's network panel shows. 100,000 views of a 2 MB page is 200 GB a month, about 6.7 GB a day or an average of 0.62 Mbit/s. Visits bunch up in busy hours, so size hosting and caching for several times that average.

### Is 1 GB 1,000 MB or 1,024 MB?

Under the SI and IEC 80000-13 prefixes, 1 GB is 1,000 MB, or 10^9 bytes, while 1 GiB (gibibyte) is 1,024 MiB, or 2^30 = 1,073,741,824 bytes. Network speeds and drive labels use decimal units. Windows counts in binary units but labels them GB, so a 50 GB file shows there as 46.57.

### “Bandwidth and download time calculator” ಎಷ್ಟು ನಿಖರವಾಗಿದೆ?

ನಿಖರತೆ ನಿಮ್ಮ ಇನ್‌ಪುಟ್‌ಗಳು ಮತ್ತು ವಿಧಾನದ ಊಹೆಗಳನ್ನು ಅವಲಂಬಿಸಿದೆ. ದಶಮಾಂಶ ಗಣನೆ 50 ಸಾರ್ಥಕ ಅಂಕೆಗಳನ್ನು ಬಳಸುತ್ತದೆ. ಆದರೆ ಅಂದಾಜುಗಳು, ಸಂಖ್ಯಾತ್ಮಕ ವಿಧಾನಗಳು ಮತ್ತು ಮೂಲ ದತ್ತಾಂಶ ಕಡಿಮೆ ನಿಖರವಾಗಿರಬಹುದು; ಪ್ರದರ್ಶಿತ ಮೌಲ್ಯಗಳನ್ನು ರೌಂಡ್ ಮಾಡುವುದರಿಂದ ಈ ಮಿತಿಗಳು ನಿವಾರಣೆಯಾಗುವುದಿಲ್ಲ. ಸ್ವತಂತ್ರ ಮೂಲಗಳ ಪರಿಹಾರಗಳೊಂದಿಗೆ ಪರಿಶೀಲಿಸಿದ ಉದಾಹರಣೆಗಳು: 6. ಉದಾಹರಣೆಗೆ, “50 GB at 100 Mbit/s with no overhead” ಅನ್ನು Python 3.8: 50e9 × 8 / 100e6 = 4000 s ಜೊತೆಗೆ ಪರಿಶೀಲಿಸಲಾಗುತ್ತದೆ.

### ಈ ವಿಧಾನದ ಮೂಲ ಯಾವುದು?

IEC 80000-13:2008 — decimal (kB, MB, GB) and binary (KiB, MiB, GiB) prefixes for bytes; IEEE 802.3 Ethernet: 8-byte preamble, 14-byte header, 1500-byte payload, 4-byte FCS and 12-byte inter-frame gap (1538 bytes per full frame); NIST — Prefixes for binary multiples.

## ಮೂಲಗಳು

- IEC 80000-13:2008 — decimal (kB, MB, GB) and binary (KiB, MiB, GiB) prefixes for bytes
- IEEE 802.3 Ethernet: 8-byte preamble, 14-byte header, 1500-byte payload, 4-byte FCS and 12-byte inter-frame gap (1538 bytes per full frame)
- [NIST — Prefixes for binary multiples](https://physics.nist.gov/cuu/Units/binary.html)