Convert Grams to Tonnes - Weight Converter
This tool converts mass from grams (g) to metric tonnes (t). The metric tonne (also spelled 'tonne') equals 1,000 kilograms and 1,000,000 grams, so the conversion is a fixed mathematical relationship.
Use this converter for quick, precise unit changes when recording weights, preparing reports, or checking calculations for supply chain, laboratory, or regulatory work. See the methodology and accuracy notes below for guidance on rounding, measurement uncertainty, and traceability.
Interactive Converter
Convert between gram and tonne with precision rounding.
Quick reference table
| Gram | Tonne |
|---|---|
| 1 g | 0 t |
| 5 g | 0 t |
| 10 g | 0 t |
| 25 g | 0 t |
| 50 g | 0.0001 t |
| 100 g | 0.0001 t |
Methodology
The conversion is based on the International System of Units (SI) definition: 1 tonne = 1,000 kilograms = 1,000,000 grams. No temperature, pressure, or material-specific correction is required for the pure unit conversion itself.
For applied work (e.g., weighing bulk materials or chemical samples) account for measurement uncertainty, balance calibration, and sample handling. Calibration traceable to national metrology institutes is recommended; follow guidance from standards organizations for documentation and uncertainty reporting.
Worked examples
1000 g → 0.001 t
5000000 g → 5 t
250 g → 0.00025 t
Key takeaways
This is an exact unit conversion: 1 t = 1,000,000 g. Use division by 1,000,000 to convert grams to tonnes.
When using measured values, include calibration status and measurement uncertainty in reports. Round results to an appropriate number of significant figures for your application.
Expert Q&A
Is the conversion exact or approximate?
The mathematical conversion between grams and metric tonnes is exact: 1 tonne = 1,000,000 grams. Any approximation arises only from rounding or from the uncertainty in measured input values.
Do I need to adjust for temperature or material density?
Not for the unit conversion itself. Temperature and density affect volume and some measurement processes, but converting mass units from grams to tonnes is independent of those factors. When converting from volume to mass, include density and temperature corrections as needed.
How many significant figures should I report?
Report results with the same number of significant figures as the least-precise measured value. For calculated conversions based on a measured mass, include the instrument's stated uncertainty and round accordingly.
What calibration or traceability should I document?
Document the balance or scale calibration certificate, calibration date, uncertainty, and traceability chain to your national metrology institute when measurements are used for compliance, invoicing, or scientific reporting.
Are there regulatory limits I should consider when reporting large masses?
Regulatory limits depend on jurisdiction and context (e.g., hazardous materials, emissions reporting). Consult relevant national and industry regulations and include measurement traceability and uncertainty when submitting figures for compliance.
Sources & citations
- NIST — SI Units and Conventions — https://www.nist.gov/pml/weights-and-measures
- ISO — Quantities and Units (ISO Catalogue) — https://www.iso.org/standards.html
- IEEE Standards Association — https://standards.ieee.org
- OSHA — Measurement and Recordkeeping — https://www.osha.gov