File Size Converter

Convert digital storage values between bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes. Toggle between binary (1024) and decimal (1000) modes to match the convention used by your operating system, drive manufacturer, or network provider.

Value to Convert

From Unit

Conversion Mode

Binary (1 KB = 1024 B) Decimal (1 KB = 1000 B)

Unit	Symbol	Value

What is a File Size Converter?

A file size converter translates digital storage quantities between different units of measurement, such as bytes, kilobytes, megabytes, gigabytes, terabytes, and petabytes. Because digital data spans an enormous range — from a single text character to entire data center archives — we use scaled units to keep numbers readable. This converter handles every common unit and lets you switch between the two competing conventions that govern how those units are defined.

The byte is the fundamental building block of digital storage, typically representing a single character of text or eight binary bits. A typical email might be a few kilobytes, a song a few megabytes, a feature film several gigabytes, and a hard drive several terabytes. As data volumes grow with higher-resolution media, larger databases, and cloud backups, units like terabytes and petabytes have become part of everyday vocabulary.

The complication with file size units is that two definitions coexist. The decimal system, favored by storage manufacturers, defines each successive unit as 1,000 times the previous one, matching the metric prefixes used in science. The binary system, favored by operating systems, uses 1,024 because computers work naturally with powers of two. The result is that a "1 TB" drive shows up as about 931 GB in your file explorer — both numbers describe the same physical storage, just using different conventions.

This converter removes that ambiguity. By toggling between binary (1,024) and decimal (1,000) modes, you can replicate the calculation performed by any software, advertisement, or technical specification. Whether you are buying storage, sizing a cloud upload, estimating bandwidth needs, or learning computer science, accurate unit conversion is essential for making sense of digital quantities.

How File Size Conversion Works

Each unit is a power of the base multiplier. To convert from one unit to another, multiply or divide by the base raised to the power of the difference in unit levels. The base is 1,024 in binary mode and 1,000 in decimal mode.

Formula Value_target = Value_source × base^{(source level − target level)}

Example

Convert 5 MB to bytes (binary mode, base 1024):

MB is 2 levels above bytes, so multiply by 1024².

5 × 1024 × 1024 = 5 × 1,048,576 = 5,242,880 bytes

Convert 5 MB to bytes (decimal mode, base 1000):

5 × 1000 × 1000 = 5,000,000 bytes

How to Use This File Size Converter

Enter your value: Type any positive number, including decimals, in the value field.
Choose the source unit: Select the unit your value is currently expressed in (B, KB, MB, GB, TB, or PB).
Pick a mode: Toggle between binary (1,024) and decimal (1,000) to match the convention you need.
Read the results table: All six unit representations are computed and displayed simultaneously for quick comparison.
Switch modes on the fly: Changing the mode instantly recalculates every value in the table, so you can compare conventions side by side.

Storage Reference & Practical Tips

Common Capacities

A typical song is 3–5 MB, a high-resolution photo 2–10 MB, a feature film 1–4 GB, a smartphone 64–512 GB, and a consumer hard drive 1–8 TB. Enterprise storage arrays routinely hold petabytes of data for backup and analytics.

Binary vs Decimal Gap

The difference between binary and decimal units grows with scale: about 2.4% at KB, 4.9% at MB, 7.4% at GB, 9.9% at TB, and 12.6% at PB. This is why a 1 TB drive appears as roughly 931 GiB in many file managers.

Network vs Storage

Network bandwidth is almost always measured in decimal bits per second (Mbps = 1,000,000 bits/s), while storage is measured in bytes. Eight bits equal one byte, so a 100 Mbps connection transfers at most about 12 MB per second in practical terms.

Use the Right Mode

Match the mode to your context: decimal for advertised drive capacity, cloud storage quotas, and bandwidth; binary for RAM, file system reports, and software that follows operating system conventions. Mismatching modes is the most common source of confusion.

Frequently Asked Questions About File Sizes

What is the difference between KB and KiB?

KB traditionally means 1,000 bytes (decimal, base 10) while KiB means 1,024 bytes (binary, base 2). Operating systems have long used KB to mean 1,024 bytes, causing confusion. The International Electrotechnical Commission introduced the KiB, MiB, GiB notation in 1998 to disambiguate, but the older KB convention remains widespread in everyday use.

Why does my hard drive show less space than advertised?

Manufacturers advertise drive sizes using decimal units (1 KB = 1,000 bytes), so a 500 GB drive has 500 billion bytes. Operating systems often display capacity in binary units (1 KiB = 1,024 bytes), making the same drive appear as about 465 GiB. This difference is a unit mismatch, not missing storage, and explains the apparent gap.

Which mode should I use, binary or decimal?

Use binary (1024) for operating system memory, RAM, and file sizes reported by Windows or Linux utilities. Use decimal (1000) for storage media capacity as advertised by hard drive and SSD manufacturers, and for network bandwidth. This converter lets you toggle between both modes so you can match the convention used by your context.

How many bytes are in a megabyte?

In decimal mode, 1 megabyte equals 1,000,000 bytes (1,000²). In binary mode, 1 mebibyte equals 1,048,576 bytes (1,024²). The difference of about 4.86% grows with each larger unit, which is why a terabyte-class drive can appear significantly smaller when displayed in binary units by the operating system.

What are the supported file size units?

This converter supports six units: bytes (B), kilobytes (KB), megabytes (MB), gigabytes (GB), terabytes (TB), and petabytes (PB). For each conversion, all six representations are computed and displayed in a table, giving you a complete picture of how your value scales across the full range of common digital storage units.

Can I convert fractional values like 1.5 GB?

Yes. The converter accepts any positive decimal value, including fractions like 1.5 GB, 0.75 MB, or 12.345 TB. Results are displayed with enough precision to convey meaningful differences, and small values are presented in scientific notation when they become too tiny to display comfortably in standard decimal form.