Steinhart-Hart Temperature

1/T = A + B×ln(R) + C×(ln(R))³

Calculator

Result
—

Formula

1/T = A + B×ln(R) + C×(ln(R))³

Description

The Steinhart-Hart equation provides a precise mathematical model for the resistance-temperature relationship of NTC thermistors. The three coefficients (A, B, C) are determined from calibration data at three known temperatures. The result T is in Kelvin and is converted to Celsius by subtracting 273.15. This equation is accurate to within ±0.02°C over a 100°C range, making it much more accurate than the simpler Beta equation, especially over wide temperature ranges. It is the standard method used in precision temperature measurement with thermistors.

Variables

  • T — Temperature in Kelvin (converted to °C in output)
  • A, B, C — Steinhart-Hart coefficients (from calibration or datasheet)
  • R — Thermistor resistance at the temperature being measured (Ω)

Practical Notes

Common 10kΩ NTC thermistor coefficients (for a typical Vishay NTCLE100E3): A = 1.009249522e-3, B = 2.378405444e-4, C = 2.019202697e-7. The simplified Beta equation (1/T = 1/T0 + (1/B)×ln(R/R0)) uses only one parameter and is accurate to ±0.5°C over a narrow range. For microcontroller implementations, a lookup table with interpolation is often more computationally efficient.

Related Formulas

ADC Resolution (LSB) ADC Theoretical SNR Wheatstone Bridge Linear Sensor Transfer Function Oversampling SNR Improvement RTD Callendar-Van Dusen

Need more features?

Save calculations, import telemetry data, simulate battery discharge, and collaborate with your team.

Try the App