ConvBolt — Unit ConverterGrams to Tonnes Converter
Converting grams to tonnes is a multiplication by a fixed factor: 1 g = 1.0000e-6 t. The table below covers the values people look up most often, and the formula section shows exactly where that factor comes from.
Because one gram works out to 1.0000e-6 t, the tonne is the far smaller unit of the two: a figure given in tonne always carries a smaller number than the same measurement in gram. A chart drawn in g can hide that, so check which label the axis uses before you compare two readings.
Where a legal or postal limit is set in tonnes, the same limit expressed in grams has to be exact — an overshoot of even one unit can change the chargeable band.
The conversion factor used here is 1.0000e-6 t per gram (7 significant digits as shown). Kept to seven figures it covers professional measurement; if you round it to two or three decimals for a spreadsheet, the error scales with the input — at a value of 1,000 g a factor rounded to three decimals can be off by a measurable amount. The reverse direction uses 1000000 g per t, the exact reciprocal, so a round trip through both pages returns your original number.
Grams to Tonnes formula
Use this formula to convert any gram value to tonnes:
Worked example: 100 g × 1.0000e-6 = 0.0001 t.
Grams to Tonnes conversion table
| Grams (g) | Tonnes (t) |
|---|---|
| 0.5 g | 5.0000e-7 t |
| 1 g | 1.0000e-6 t |
| 2 g | 2.0000e-6 t |
| 5 g | 5.0000e-6 t |
| 10 g | 1.0000e-5 t |
| 20 g | 2.0000e-5 t |
| 50 g | 5.0000e-5 t |
| 100 g | 0.0001 t |
| 500 g | 0.0005 t |
| 1000 g | 0.001 t |
How to convert grams to tonnes
Multiply the gram value by 1.0000e-6 to get the equivalent in tonnes. This single factor works for every value in the table above and for anything else you need — there is no per-value adjustment, which is why a conversion table and a calculator always agree.
If you need the opposite direction, use the Tonnes to Grams converter instead of dividing by hand; both pages use the same source factors. For every other g conversion in one place, see the g conversion hub.
Frequently asked questions
How many tonnes are in 1 gram?
1 gram = 1.0000e-6 t.
What is 100 grams in tonnes?
100 g = 0.0001 t.
Is converting grams to tonnes the same as tonnes to grams?
No — the direction changes the multiplier. The reverse conversion (1 t = 1000000 g) is on the Tonnes to Grams page.
Related conversions
Try the ConvBolt Unit Converter for any other weight unit, browse the Weight conversions, or read our conversion guides.