Tesla to Gauss
1 Tesla (T) = 10,000Gauss (G)
By KAMP Inc. / UnitOwl · Last reviewed:
How Many Gauss in a Tesla?
To convert tesla to gauss, multiply the tesla value by 10,000. The formula is G = T × 10,000. For example, 1 tesla equals exactly 10,000 gauss. This conversion is one of the most commonly needed in magnetism and electromagnetism. The tesla is the SI unit of magnetic flux density (also called magnetic induction), while the gauss is the corresponding CGS unit that remains widely used in many practical applications. Geophysicists measuring Earth's magnetic field, engineers designing magnetic shielding, medical physicists calibrating MRI machines, and hobbyists testing permanent magnets all encounter situations where they need to move between tesla and gauss. The clean factor of 10,000 makes mental arithmetic straightforward, but the sheer size difference between the units means that confusing them can lead to catastrophic errors in any magnetic field calculation. It also matters whenever a specification uses millitesla but the handheld instrument reads gauss or milligauss. In safety work, procurement, and lab reporting, getting the unit right is often just as important as getting the number right. That is why magnetics teams usually keep a few anchor values memorized before they trust any converted result.
How to Convert Tesla to Gauss
- Identify the magnetic flux density value in tesla (T) that you want to convert.
- Multiply the tesla value by 10,000 to get the equivalent in gauss (G).
- The result is the magnetic flux density in gauss.
- For millitesla (mT), multiply by 10 to get gauss (since 1 mT = 10 G).
- For microtesla (µT), divide by 100 to get gauss (since 1 µT = 0.01 G), or equivalently, 1 µT = 10 milligauss.
Real-World Examples
Quick Reference
| Tesla (T) | Gauss (G) |
|---|---|
| 1 | 10,000 |
| 2 | 20,000 |
| 3 | 30,000 |
| 5 | 50,000 |
| 10 | 100,000 |
| 15 | 150,000 |
| 20 | 200,000 |
| 25 | 250,000 |
| 50 | 500,000 |
| 75 | 750,000 |
| 100 | 1,000,000 |
| 250 | 2,500,000 |
| 500 | 5,000,000 |
| 1,000 | 10,000,000 |
History of Tesla and Gauss
The gauss was named after Carl Friedrich Gauss, the German mathematician and physicist who made pioneering measurements of Earth's magnetic field in the 1830s. Gauss developed the first absolute method for measuring magnetic field intensity and established the CGS unit that bears his name. For over a century, the gauss was the standard unit in magnetism research, and vast quantities of scientific data are recorded in gauss. The tesla was introduced as the SI unit of magnetic flux density at the 1960 General Conference on Weights and Measures, named after Nikola Tesla, the Serbian-American inventor and electrical engineer who made foundational contributions to alternating current power systems and electromagnetic devices. The tesla is defined as one weber per square meter, or equivalently, one kilogram per ampere per second squared — tying it neatly into the SI framework. The factor of 10,000 between tesla and gauss comes from the CGS-to-SI conversion for magnetic quantities. In CGS electromagnetic units, the base units are centimeter, gram, and second, while SI uses meter, kilogram, and second. The particular factor of 10⁴ arises from the combination of length and mass unit differences in the electromagnetic context. Today, the tesla dominates in physics publications, MRI technology, and engineering specifications, while the gauss persists in geophysics, everyday magnetometer readings, and practical electromagnetic compatibility work.
Common Mistakes to Avoid
- Dividing instead of multiplying. To convert tesla to gauss, multiply by 10,000. Dividing gives a value 100 million times too small.
- Confusing magnetic flux density (tesla, gauss) with magnetic field strength (A/m, oersted). In free space they are proportional, but in magnetic materials the distinction matters enormously.
- Forgetting prefix conversions. When working with millitesla or microtesla, apply the metric prefix before multiplying by 10,000, or use the shortcuts: 1 mT = 10 G, 1 µT = 10 mG.
- Comparing values measured at different positions and assuming the unit conversion caused the mismatch. A magnet's surface field, center-bore field, and stray field can differ dramatically even before any tesla-to-gauss conversion is applied.
Frequently Asked Questions
How many gauss are in one tesla?
Why do people still use gauss when tesla is the SI standard?
What is a dangerously strong magnetic field?
How strong is a refrigerator magnet in tesla?
What is 1 millitesla in gauss?
The clean factor of 10,000 between tesla and gauss makes mental conversion easy. Just move the decimal point four places. But watch the metric prefixes: most practical measurements are in millitesla (mT) or microtesla (µT), not plain tesla. Keep these handy equivalences in mind: 1 T = 10,000 G, 1 mT = 10 G, 1 µT = 0.01 G = 10 mG. Earth's field is about 500 mG = 50 µT = 0.5 G = 0.00005 T.
Sources & References
- NIST — Units and Conversion Factors — Official unit conversion factors from the National Institute of Standards and Technology.
- BIPM — The International System of Units (SI) — International SI unit definitions from the International Bureau of Weights and Measures.