Data size converter
Compare bits and bytes with explicitly decimal and binary storage units.
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How it works
Convert a data-size quantity between bits, eight-bit bytes, decimal SI byte prefixes and explicitly labeled binary byte prefixes. Decimal gigabytes and binary gibibytes remain separate units rather than sharing an ambiguous GB label.
A few things to know
Numeric size conversion, not a file inspection or transfer-time estimate. Decimal kB/MB/GB use powers of 1000; KiB/MiB/GiB use powers of 1024. Fractional units are allowed as arithmetic equivalents but do not represent a physical fractional bit. Large counts are floating-point estimates, not exact integer storage accounting. Display uses up to 12 significant digits; this is not arbitrary-precision arithmetic or a measurement calibration. Numeric magnitude is bounded to 1e100, with nonzero inputs at least 1e-100.
When to use this tool
Storage sizes can look inconsistent when one source uses decimal gigabytes and another uses binary gibibytes. This data-size converter makes that distinction explicit: kB through PB use powers of 1,000, while KiB through PiB use powers of 1,024. It also distinguishes eight-bit bytes from bits. Enter a numeric data amount and choose the source definition rather than relying on an ambiguous label. The result is an arithmetic equivalent, not a measurement of a file, disk’s usable capacity or transfer overhead.
- Compare decimal storage-capacity figures with explicitly binary values.
- Translate a file-size limit between MB and MiB before preparing an upload.
- Check bit-to-byte arithmetic while preserving the difference between size and transfer rate.
How to use data size converter
Enter the stated data amount
Put the number in Value without B, bit or a prefix. Decimal and scientific notation are supported; there is no file upload or size inspection.
Choose the actual size definition
Select From unit. MB means 1,000,000 bytes, while MiB means 1,048,576 bytes. Choose Bits only when the original quantity is measured in bits.
Read a clearly labeled equivalent
Choose To unit and calculate. Review Converted value, use the full table for comparison and download the equivalent-size CSV if needed.
A decimal gigabyte in binary units
Inputs
Value 1; From unit Gigabytes (GB, 1000³ B); To unit Gibibytes (GiB, 1024³ B).
Result
Converted value is 0.931322574615 GiB. The table shows 1,000,000,000 bytes for the same amount.
What it means
A GiB contains 1,073,741,824 bytes, so the smaller decimal billion-byte amount is about 0.9313 GiB. No data has disappeared; the number changes because the chosen unit is larger.
Common mistakes to avoid
Treating MB and MiB as synonyms
They use different bases. Confirm the service’s actual limit or device’s stated convention before selecting one.
Confusing bits with bytes
Eight bits equal one byte in this tool. A lowercase b in a source can matter, but the converter uses explicit unit labels.
Assuming converted size equals usable capacity
Formatting, reserved space and filesystem overhead are not measured. A numeric conversion cannot establish the available storage on a device.
Frequently asked questions
Definitions, edge cases, and practical next steps for this tool. Search all tool FAQs ↗
What is the difference between decimal and binary prefixes?
Decimal byte prefixes use powers of 1,000, while binary prefixes use powers of 1,024. For example, kB is 1,000 bytes and KiB is 1,024 bytes. The labels remain separate so the chosen convention is visible in the result.
How many bits are in a byte?
The converter uses an eight-bit byte, so one byte equals eight bits. It converts size quantities with that fixed relationship. Historical machine word sizes and architecture-specific units are not included, and words should not be assumed to equal bytes.
Why is one GB less than one GiB?
A decimal GB is one billion bytes, while a binary GiB is 1,073,741,824 bytes. Expressing the same billion bytes in a larger unit produces a number below one. This difference is a unit convention rather than a loss or compression effect.
Does this inspect the size of my file?
No. There is no file field, and the converter does not access your filesystem. Enter a size reported by your device or service and choose its definition. The image compression tool is a separate tool for generating a smaller image file.
Can I use this to calculate download time?
It can convert a known size, but it does not model transfer speed or time. A rate such as megabits per second is size per duration, not a size alone. Network overhead and changing throughput also require separate assumptions.
Are fractional bytes or bits allowed?
Fractional numeric values are allowed as arithmetic equivalents. They should not be interpreted as a physically stored fraction of a bit. This is useful when comparing unit scales, while actual file storage and allocation may require whole-unit accounting.
How should I handle an ambiguous KB label?
Check the source’s definition. This tool uses kB for the decimal definition and KiB for the binary definition. It cannot infer what a different application means by KB, so choose only after confirming whether that source counts 1,000 or 1,024 bytes.
Are very large byte counts exact?
The calculation uses floating-point arithmetic and displays up to 12 significant digits. Large integer counts can lose exact single-byte precision. Use an exact integer-based accounting method if every byte must reconcile, and use this converter for understandable unit comparisons.
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Sources and method
Use the references below to check definitions and platform guidance. The model’s scope and limits are explained above. Read our editorial standards.