Loading page
About this tool
Convert bytes, bits, kB/MB/GB/TB and KiB/MiB/GiB/TiB in one place, and see why a 1 TB drive shows as 931 GiB.
Byte Converter turns one size into all 15 supported units at once: bits through gigabits, SI decimal bytes (kB, MB, GB, TB, PB — powers of 1000) and IEC binary bytes (KiB, MiB, GiB, TiB, PiB — powers of 1024). Each unit is stored as its exact byte factor, so your input is normalised to a single byte total and then divided into every target unit — one division per row, with no chained rounding. Both prefix families, and the fixed 8-bits-per-byte octet, come from IEC 80000-13, which is why the tool keeps kB and KiB visibly apart instead of treating them as the same thing. The whole calculation is plain JavaScript running in your browser: no upload, no API call, no account.
Open Byte Converter on AltFTool — it loads instantly in your browser.
Type the size into the Size field and pick its unit from the menu — the options are grouped into Bits, Decimal (×1000) and Binary (×1024).
Read the total in bytes, the human-readable binary and decimal forms, and the full table of all 15 units, which recalculates as you type.
Enter a link speed in Mbps for a transfer-time estimate, or press Copy result to put every converted value on your clipboard.
Decimal and binary values for the same size sit in one table with a Group column, so the 1000-versus-1024 gap is visible rather than guessed at.
Link speeds are quoted in bits and file sizes in bytes. Both appear together at a fixed 8 bits per byte, plus a transfer-time readout for any Mbps figure you enter.
Sizes above 2^53 bytes, negative values and non-numeric input return a plain-language message instead of a silently rounded or NaN result.
The conversion is arithmetic in your browser — no file upload, no server request, no sign-up, and no usage limit.
Because the manufacturer counts a terabyte as 1,000,000,000,000 bytes, while Windows divides by 1024 three times and still writes the label "GB". 1,000,000,000,000 ÷ 1024³ = 931.32, so the same drive is honestly 1 TB and 931.32 GiB. No capacity is missing — the two labels just use different bases.
1 MB is 1,000,000 bytes and 1 MiB is 1,048,576 bytes, so MiB is 4.86% larger. The binary prefixes (kibi, mebi, gibi) were standardised in IEC 60027-2 and carried into IEC 80000-13 precisely so a power-of-1024 quantity has its own name. Drive makers, network gear and macOS mean the decimal MB; Windows and most RAM specs mean MiB even when they print "MB".
1,000,000,000 bytes in a decimal gigabyte (GB), and 1,073,741,824 bytes in a binary gibibyte (GiB) — a 7.4% difference. This converter shows both rows for the same input, so you can pick whichever one your operating system or spec sheet actually means.
8, universally in modern computing — IEC 80000-13 defines the byte as an 8-bit octet. That is why a 100 Mbps connection moves at most 12.5 MB per second: 100,000,000 bits ÷ 8 = 12,500,000 bytes.
About 376 seconds, or 6 minutes 16 seconds, at the theoretical line rate. The tool computes it as bytes × 8 ÷ (Mbps × 1,000,000), so 4.7 GB is 37,600,000,000 bits over a 100,000,000 bit/s link. Real transfers run slower because of protocol overhead and shared bandwidth.
The ceiling is 2^53 − 1 bytes, or 9,007,199,254,740,991 — the largest integer a JavaScript number represents exactly. Past that, conversions start dropping low-order digits, so the tool returns an error rather than a figure that looks precise but isn't.
Yes it's free with no sign-up, and nothing is uploaded. Every conversion is arithmetic performed in your browser; there are no network requests in the tool, so the numbers you type never reach a server. It also keeps working on a page you already have open if your connection drops.
15 in total: bit, kilobit, megabit and gigabit; the decimal bytes B, kB, MB, GB, TB and PB; and the binary bytes KiB, MiB, GiB, TiB and PiB. Enter a size in any one of them and every other unit updates in the same table, with a Copy button that puts the full list on your clipboard.
Add the Byte Converter widget to your blog or website — free, responsive, no signup. Just keep the “Widget by AltFTool” credit link visible.
<iframe src="https://www.altftool.com/embed/widget/byte-converter"
title="Byte Converter — free AltFTool widget"
width="100%" height="640" style="border:0;border-radius:12px;overflow:hidden"
loading="lazy" referrerpolicy="no-referrer-when-downgrade" allow="clipboard-write"></iframe>
<p style="font-size:12px;margin:4px 0 0">Widget by <a href="https://www.altftool.com/tools/all/byte-converter?utm_source=embed&utm_medium=widget" rel="nofollow">AltFTool — free online tools</a></p>