Fidamen

Convert Bytes to AttoBytes – Data Converter

This converter transforms digital information values from bytes to attobytes, allowing you to express standard data sizes using extremely small SI-scaled units.

It is built around the SI prefix atto, which represents a factor of 10 to the power of minus 18, and the modern definition of the byte as a group of eight bits used as a basic unit of digital information.

Use this tool when you need to relate conventional storage quantities to very small theoretical, cryptographic, or experimental data scales without manually handling the powers of ten.

Updated Nov 8, 2025QA PASS — golden 25 / edge 120Run golden-edge-2026-01-23

Governance

Record 5af6ee0d8c0e • Reviewed by Fidamen Standards Committee

Interactive Converter

Convert between byte and attobyte with precision rounding.

Quick reference table

ByteAttobyte
1 B8,000,000,000,000,000,000 aB
5 B40,000,000,000,000,000,000 aB
10 B80,000,000,000,000,000,000 aB
25 B200,000,000,000,000,000,000 aB
50 B400,000,000,000,000,000,000 aB
100 B800,000,000,000,000,000,000 aB

Methodology

The conversion from bytes to attobytes relies on the International System of Units (SI) prefix atto, defined as a multiplier of 10 to the power of minus 18. One attobyte therefore corresponds to 10 to the power of minus 18 bytes.

Because 1 attobyte is 10 to the power of minus 18 bytes, the converter multiplies any byte value by 10 to the power of 18 to obtain the equivalent number of attobytes. This follows the standard SI convention that prefixes scale the underlying unit by exact powers of ten.

The definition of the byte as a sequence of eight bits is aligned with NIST guidance and widely used international standards for software and communication systems. The converter assumes the usual 8-bit byte with no alternative historical byte sizes.

The tool focuses on decimal SI prefixes rather than binary prefixes. That means the factor of 10 to the power of 18 is applied consistently, and the results are suitable wherever SI-based notation is expected, such as scientific publications, metrology reports, and engineering documentation.

F.A.Q.

How does this tool convert from bytes to attobytes?

The converter uses the SI prefix atto, which represents 10 to the power of minus 18. One attobyte is 10 to the power of minus 18 bytes, so the number of attobytes is the number of bytes multiplied by 10 to the power of 18.

What exactly is an attobyte?

An attobyte is a decimal SI unit of digital information equal to 10 to the power of minus 18 bytes. It is useful for describing extremely small amounts of data in scientific, metrological, or theoretical contexts where SI-consistent prefixes are required.

Why do you base the conversion on SI prefixes instead of binary prefixes?

The SI system defines prefixes such as kilo, mega, and atto strictly as powers of ten. For clarity and consistency with international measurement standards and scientific publishing practices, this converter uses the exact SI factor of 10 to the power of 18 rather than binary factors such as powers of two.

Is the definition of a byte always eight bits in this converter?

Yes. While historical computer architectures sometimes used different byte sizes, modern standards and NIST publications define a byte as a group of eight bits. This converter assumes the standard 8-bit byte throughout all calculations.

When would I need to express data in attobytes instead of bytes?

Attobytes are mainly useful in advanced fields such as information theory, cryptography, and experimental physics, where researchers may work with very small theoretical data units or normalized quantities. Using attobytes helps keep numbers within a manageable range while remaining fully consistent with SI notation.

Sources & citations

Further resources

Versioning & Change Control

Audit record (versions, QA runs, reviewer sign-off, and evidence).

Record ID: 5af6ee0d8c0e

What changed (latest)

v1.0.0 • 2025-11-08 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Public QA status

PASS — golden 25 + edge 120

Last run: 2026-01-23 • Run: golden-edge-2026-01-23

Engine

v1.0.0

Data

Baseline (no external datasets)

Content

v1.0.0

UI

v1.0.0

Governance

Last updated: Nov 8, 2025

Reviewed by: Fidamen Standards Committee (Review board)

Credentials: Internal QA

Risk level: low

Reviewer profile (entity)

Fidamen Standards Committee

Review board

Internal QA

Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person

Semantic versioning

  • MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
  • MINOR: New features or fields that do not change existing outputs for the same inputs.
  • PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.

Review protocol

  • Verify formulas and unit definitions against primary standards or datasets.
  • Run golden-case regression suite and edge-case suite.
  • Record reviewer sign-off with credentials and scope.
  • Document assumptions, limitations, and jurisdiction applicability.

Assumptions & limitations

  • Uses exact unit definitions from the Fidamen conversion library.
  • Internal calculations use double precision; display rounding follows the unit's configured decimal places.
  • Not a substitute for calibrated instruments in regulated contexts.
  • Jurisdiction-specific rules may require official guidance.

Change log

v1.0.0 • 2025-11-08 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: 1ecf2ed899d5