Thermistor Calculator – NTC Beta R to T
Resistance ↔ temperature with the Beta approximation
Required Parameters
Waiting for input data...
Temperature Conversion Hub
Direction converters, charts, formulas, and engineering thermal tools.
Converters
Main tool
Common temperatures
Tables & formulas
Quick Answer
With R = R0, T = T0. Typical bench values: 10 kΩ at 25°C, β ≈ 3950 K. The Beta equation is an approximation with a limited temperature range — not a precision R–T curve for every NTC.
Thermistor Calculator
This tool uses the Beta approximation for an NTC. Enter the part’s R0, T0, and β from the datasheet.
1/T = 1/T0 + (1/β) ln(R/R0) (T in kelvin)
Limits
- Results change if you change β, R0, or T0. There is no universal NTC curve.
- β is specified over a temperature interval. Outside that interval the error grows.
- Different vendors publish different R–T tables even when β looks similar.
- This is not a model for PTCs or RTDs (Pt100 / Pt1000).
Many hobby dividers pair a 10 kΩ NTC with a 10 kΩ resistor. Identify the fixed resistor with the Resistor Color Code Calculator and size the divider on the Voltage Divider Calculator.
Related
- Temperature Converter
- 10k ohm resistor color code — common fixed-leg value
Design Notes
This uses the Beta approximation for an NTC. Results depend on the specific thermistor parameters, the temperature range where β is specified, and the manufacturer R–T curve. It is not a high-accuracy model for every NTC.
Common Mistakes
- 1
Treating a single β as accurate over the full datasheet range.
- 2
Entering T0 in kelvin while the field expects Celsius, or the reverse.
- 3
Using the Beta model for a PTC or an RTD.
Knowledge Base
What is the thermistor Beta equation?
1/T = 1/T0 + (1/β) ln(R/R0), with T and T0 in kelvin. Solving for R: R = R0 · exp(β (1/T − 1/T0)).
How accurate is the Beta model?
It is a two-point approximation. Accuracy is best near T0 and inside the β temperature window on the datasheet. Manufacturer R–T tables can differ.