# Billion to Trillion Converter URL: https://speedycalculator.com/calculators/conversion/billion-to-trillion-converter/ Last updated: 2026-10-25 > Convert billion (billion) to trillion (trillion): 1 billion = 0.001 trillion, so multiply by 0.001 or divide by 1,000. Both fields are editable, so you can also type in trillion and get billion back. ## Inputs - Billion (billion) ## Results - Trillion ## Formula ``` 1 billion = 0.001 trillion 1 trillion = 1,000 billion trillion = billion × 0.001 ``` ## Explanation In the short scale used in English today, a trillion is a thousand billion (10¹²). Government budgets and company valuations often move between the two. ### How to use the Billion to Trillion Converter - Type the number of billion into the **Billion** field. Decimals such as 500 are fine. - Read the answer in **Trillion** – it updates as you type, with no button to press. - To convert the other way, type into **Trillion** and the billion are recalculated. - Press **Copy results** to copy both values with the page title, or **Copy link** to share this exact conversion. This page converts only billion ⇄ trillion. Need a different unit? Use the general number converter, where you can choose any “from” and “to” unit. ### How it works Both units measure number, so they are always in the same ratio: one billion equals 0.001 trillion. The calculator multiplies the number of billion you type by 0.001 to give trillion, and when you type into the trillion field it divides by the same factor to give billion. Because the ratio never changes, doubling the billion always doubles the trillion. Results are calculated at full precision and rounded only for display (up to eight decimal places, with very large or small values shown in scientific notation). ### How to convert billion to trillion - Write down the value in billion, for example **1,000 billion**. - Multiply by the conversion factor 0.001 (because 1 billion = 0.001 trillion). - 1,000 × 0.001 = **1 trillion**. - To go back from trillion to billion, divide by 0.001 – or multiply by 1,000. ### billion to trillion conversion table BillionTrillionTrillionBillion1 billion0.001 trillion1 trillion1,000 billion10 billion0.01 trillion2 trillion2,000 billion100 billion0.1 trillion5 trillion5,000 billion500 billion0.5 trillion10 trillion10,000 billion1,000 billion1 trillion20 trillion20,000 billion2,500 billion2.5 trillion50 trillion50,000 billion10,000 billion10 trillion100 trillion100,000 billion1,000 trillion1,000,000 billion ### What is a billion? A billion is 10⁹ (1,000,000,000) in the short scale used in English today, equal to 100 crore. ### What is a trillion? A trillion is 10¹² in the short scale, a thousand billion. ### Common mistakes to avoid Misreading south asian digit grouping (1,00,00,000) as international grouping, and the old british “long scale” billion (10¹²), no longer in use. ## Worked example Inputs — Billion: 1,000 billion. Results — **Trillion = 1 trillion**. ## FAQ **How many billions in a trillion?** 1,000. **What is 2,500 billion?** 2.5 trillion. **How many trillion are in one billion?** 1 billion = 0.001 trillion. **How many billion are in one trillion?** 1 trillion = 1,000 billion. **How do I convert billion to trillion?** Multiply the number of billion by 0.001. For example, 1,000 billion × 0.001 = 1 trillion. **How do I convert trillion back to billion?** Divide by 0.001 (or multiply by 1,000), or simply type the value into the trillion field above. **What is 10 billion in trillion?** 10 billion = 0.01 trillion. **What is 100 billion in trillion?** 100 billion = 0.1 trillion. **Is this conversion exact?** Yes. The factor comes from the official definitions of both units (NIST and the SI), so the only difference you may see is rounding in the last displayed digit. **Can I convert to other units on this page?** This page converts only between billion and trillion. To pick any number unit, use the general number converter linked under Related calculators. **What formula does the Billion to Trillion Converter use?** 1 billion = 0.001 trillion. ## Sources - [NIST Special Publication 811 – Guide for the Use of the International System of Units](https://www.nist.gov/pml/special-publication-811) - [NIST Handbook 44 Appendix C – General tables of units of measurement](https://www.nist.gov/pml/owm/nist-handbook-44-current-edition)