Fidamen

Convert Ounces to Grams – Weight Converter

This converter converts a value in ounces to grams using the internationally recognized definition of the avoirdupois ounce. It is intended for everyday conversions as well as for laboratory and regulatory contexts where clarity about unit type and precision matters.

The tool distinguishes common practical considerations: which ounce type is in use, how many significant digits to report, and when to consider measurement uncertainty. When accuracy or compliance is required, follow calibration and reporting guidance from standards organizations.

Updated Nov 28, 2025QA PASS — golden 25 / edge 120Run golden-edge-2026-01-23

Governance

Record eb3c4f15dc5b • Reviewed by Fidamen Standards Committee

Interactive Converter

Convert between ounce and gram with precision rounding.

Quick reference table

OunceGram
1 oz28.3495 g
5 oz141.7476 g
10 oz283.4952 g
25 oz708.7381 g
50 oz1,417.4762 g
100 oz2,834.9523 g

Methodology

Definition used: 1 avoirdupois ounce equals exactly 28.349523125 grams. This conversion factor is the standard for common mass measurements and trade in countries using avoirdupois units.

For troy ounces (used for precious metals) a different conversion applies: 1 troy ounce = 31.1034768 grams. The converter defaults to the avoirdupois ounce; choose a troy-ounce aware tool when working with bullion or gemstones.

Accuracy guidance: observe calibration and uncertainty practices from national metrology guidance. For traceable measurements, use calibrated balances and report uncertainty according to NIST/ISO guidelines. Round results only after considering required significant figures for your use case.

Worked examples

1.0 oz → 28.349523125 g → report as 28.35 g if two decimal places are required

8.0 oz → 226.79618499999998 g → report as 226.80 g when rounding to two decimals

2.5 oz → 70.8738078125 g → report as 70.874 g when rounding to three decimals

F.A.Q.

Which ounce does this converter use?

By default this converter uses the avoirdupois ounce (1 oz = 28.349523125 g). For precious metals priced by the troy ounce, use the troy conversion (1 troy oz = 31.1034768 g).

Why are different ounce values used in some contexts?

There are multiple historical definitions of the ounce. The two most common today are the avoirdupois ounce for general mass and the troy ounce for precious metals. Always confirm which ounce type your context requires.

How many decimal places should I report?

Report the number of decimal places or significant digits appropriate to your task. For cooking, two decimal places are usually sufficient. For laboratory or regulatory reporting, follow your lab's SOP and NIST/ISO uncertainty requirements.

Does this converter account for measurement error from my scale?

No. This tool performs exact mathematical unit conversion. It does not include measurement uncertainty from instruments. For traceable results, use a calibrated balance and include uncertainty following NIST and ISO guidance.

Is the conversion factor exact?

The avoirdupois ounce to gram factor used here is the defined value used in international practice. Measurement results will still be subject to instrument uncertainty and sampling error when weighing physical objects.

Are there safety or regulatory considerations when weighing materials?

Yes. Follow workplace safety and handling rules relevant to the material being weighed. For regulated substances or workplace exposure limits, consult safety standards and regulatory agencies for handling, calibration, and recordkeeping requirements.

Sources & citations

Further resources

Versioning & Change Control

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

Record ID: eb3c4f15dc5b

What changed (latest)

v1.0.0 • 2025-11-28 • 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 28, 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 • 2025-11-28 • 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: 627afced9beb