Mathematics · Differential Equations

Newton's Law of Cooling Calculator

Estimate an object's temperature as it approaches a constant ambient temperature.

Runs locally
Your numbers

Inputs and results stay in this browser. Change one value at a time to explore the relationship.

Your inputCalculatedPassed forward in chains
Temperature T(t)45.751561
Difference from ambient25.751561
Decay factor0.367879

Calculation steps

  1. Initial difference = 9020=70.
  2. Decay factor = e^(−0.1×10)=0.36787944117144233.
  3. T(10)=20+70×0.36787944117144233=45.75156088200096.

Understand Newton cooling

One idea, three depths

Choose how deeply to explain Newton cooling

Newton cooling: Estimate an object's temperature as it approaches a constant ambient temperature.

Age 5Explain it to a 5-year-oldStart with a picture

Imagine using Newton cooling to answer this question: estimate an object's temperature as it approaches a constant ambient temperature? Enter Initial temperature T₀, Ambient temperature Tₐ, Cooling constant k, and 1 other input; the calculator shows Temperature T(t). For example: An object at 90°C in a 20°C room with k=0.1 after 10 minutes is about 45.75°C. The answer tells you Temperature T(t).

Age 15Explain it to a 15-year-oldConnect it to the formula

The temperature changes at a rate proportional to its difference from the surroundings, so that difference decays exponentially. The rule is T(t)=Tₐ+(T₀−Tₐ)e⁻ᵏᵗ. Its input values are Initial temperature T₀, Ambient temperature Tₐ, Cooling constant k, Time t, and the main result is Temperature T(t). For example: An object at 90°C in a 20°C room with k=0.1 after 10 minutes is about 45.75°C.

CollegeExplain it at college levelState the model precisely

This calculator evaluates the stated newton cooling relation over the valid real-number domain stated below. The implemented relation is T(t)=Tₐ+(T₀−Tₐ)e⁻ᵏᵗ, evaluated from Initial temperature T₀, Ambient temperature Tₐ, Cooling constant k, Time t to produce Temperature T(t). The temperature changes at a rate proportional to its difference from the surroundings, so that difference decays exponentially. The model approaches ambient temperature; it does not normally cross it.

Inputs and valid domain

  • Initial temperature T₀ must be a finite real number.
  • Ambient temperature Tₐ must be a finite real number.
  • Cooling constant k must be a finite real number, at least 0.
  • Time t must be a finite real number, at least 0.

Important boundary: The model approaches ambient temperature; it does not normally cross it.

The formula

T(t)=Tₐ+(T₀−Tₐ)e⁻ᵏᵗ

How the calculator works through it

It substitutes Initial temperature T₀, Ambient temperature Tₐ, Cooling constant k, Time t into the formula and exposes every numerical step above. The main output is Temperature T(t), accompanied by Difference from ambient, Decay factor.

Read the result correctly

The Temperature T(t) is the direct answer to “estimate an object's temperature as it approaches a constant ambient temperature.” Read it with the units shown beside the inputs; a sign, angle, percentage or rate changes what the number means.

A worked check

An object at 90°C in a 20°C room with k=0.1 after 10 minutes is about 45.75°C.

Where this model stops being reliable

The model approaches ambient temperature; it does not normally cross it.

Learn it by changing one value

Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.

Dictionary terms behind this calculator

Before studying the codeWhat you should know firstUse the calculator immediately, or check the foundations before reading the implementation.

These foundations help you understand why Newton cooling works. They never block the calculator, and “optional” means useful context rather than a hidden requirement.

Hard requirements

  • Reading formulas and substituting values

    Newton cooling uses T(t)=Tₐ+(T₀−Tₐ)e⁻ᵏᵗ. You need to recognise what each side represents before substituting the stated inputs or rearranging the relationship.

    Review this foundation about 4 min

Strong support

Optional enrichment

Learn the missing foundationsI already know these — show the code

Mathematics → algorithm → program

Implement this calculation in code

These are direct reference implementations of the calculator's principal relationship and first output. They run locally and include a small known-answer check where the language supports it.

Algorithm

  1. Read Initial temperature T₀, Ambient temperature Tₐ, Cooling constant k, Time t.
  2. Evaluate the principal relationship: T(t)=Tₐ+(T₀−Tₐ)e⁻ᵏᵗ.
  3. Return Temperature T(t) and check the domain conditions described above.
Python
            from math import *

def newton_cooling_ode(a, b, r, x) -> float:
    return (b + ((a - b) * exp((-(r * x)))))

assert abs(newton_cooling_ode(90, 20, 0.1, 10) - 45.75156088200096) < 1e-6 * max(1.0, abs(45.75156088200096))
          
Current calculator valuesUpdates when you change an input above.
              
            
C
            #include <assert.h>
#include <math.h>

double newton_cooling_ode(double a, double b, double r, double x) {
    return (b + ((a - b) * exp((-(r * x)))));
}

int main(void) {
    const double expected = 45.75156088200096;
    const double actual = newton_cooling_ode(90, 20, 0.1, 10);
    assert(fabs(actual - expected) < 1e-6 * fmax(1.0, fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
C++
            #include <cassert>
#include <cmath>
#include <numbers>

double newton_cooling_ode(double a, double b, double r, double x) {
    return (b + ((a - b) * std::exp((-(r * x)))));
}

int main() {
    constexpr double expected = 45.75156088200096;
    const double actual = newton_cooling_ode(90, 20, 0.1, 10);
    assert(std::fabs(actual - expected) < 1e-6 * std::fmax(1.0, std::fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
Linux x86-64 assembly

x86-64 NASM · System V ABI · Linux · SSE2 with libm where required

            ; double newton_cooling_ode(double a, double b, double r, double x)
; Linux x86-64 NASM · System V ABI · first eight doubles in xmm0–xmm7
extern exp
global newton_cooling_ode
section .text

newton_cooling_ode:
    push rbp
    mov rbp, rsp
    sub rsp, 80
    movsd [rbp-8], xmm0
    movsd [rbp-16], xmm1
    movsd [rbp-24], xmm2
    movsd [rbp-32], xmm3
    movsd xmm0, [rbp-8]
    subsd xmm0, [rbp-16]
    movsd [rbp-56], xmm0
    movsd xmm0, [rbp-24]
    mulsd xmm0, [rbp-32]
    movsd [rbp-80], xmm0
    pxor xmm0, xmm0
    subsd xmm0, [rbp-80]
    movsd [rbp-72], xmm0
    movsd xmm0, [rbp-72]
    call exp wrt ..plt
    movsd [rbp-64], xmm0
    movsd xmm0, [rbp-56]
    mulsd xmm0, [rbp-64]
    movsd [rbp-48], xmm0
    movsd xmm0, [rbp-16]
    addsd xmm0, [rbp-48]
    movsd [rbp-40], xmm0
    movsd xmm0, [rbp-40]
    leave
    ret
          
Current calculator valuesUpdates when you change an input above.
              
            
MATLAB
            function result = newton_cooling_ode(a, b, r, x)
    result = (b + ((a - b) * exp((-(r * x)))));
end
          
Current calculator valuesUpdates when you change an input above.
              
            
Wolfram Language
            ClearAll[mwCalculate];
mwCalculate[a_, b_, r_, x_] := (b + ((a - b) * Exp[(-(r * x))]));
          
Current calculator valuesUpdates when you change an input above.
              
            

Continue in mathematical software

The downloaded file includes your current inputs and first calculated result. It is created locally.

Floating-point answers can differ slightly by language, compiler and processor. Compare within a suitable tolerance rather than assuming every decimal representation will be identical.

Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations

Standards, reading and academic references

Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.

Calculus Volume 1

Read OpenStax Calculus: Derivatives and integration
Cite this book
APA 7
Strang, G., & Herman, E. (2016). Calculus volume 1. OpenStax. https://openstax.org/books/calculus-volume-1/pages/1-introduction
MLA 9
Strang, Gilbert, and Edwin Herman. Calculus Volume 1. OpenStax, 2016, https://openstax.org/books/calculus-volume-1/pages/1-introduction.
Chicago author-date
Strang, Gilbert, and Edwin Herman. 2016. Calculus Volume 1. Houston, TX: OpenStax. https://openstax.org/books/calculus-volume-1/pages/1-introduction.

OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.

Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS

These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.

APA 7

MW SysArc. (2026, July 21). Newton's Law of Cooling Calculator. MW SysArc Tools. https://math.mwsysarc.com/differential-equations/newton-cooling

MLA 9

MW SysArc. “Newton's Law of Cooling Calculator.” MW SysArc Tools, 21 July 2026, https://math.mwsysarc.com/differential-equations/newton-cooling. Accessed 31 Aug. 2026.

Chicago 17

MW SysArc. “Newton's Law of Cooling Calculator.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://math.mwsysarc.com/differential-equations/newton-cooling.

Harvard

MW SysArc (2026) ‘Newton's Law of Cooling Calculator’, MW SysArc Tools. Published 21 July 2026. Available at: https://math.mwsysarc.com/differential-equations/newton-cooling (Accessed: 31 August 2026).

BibTeX and RIS records

BibTeX

@misc{mwsysarc_newton_cooling_ode_2026,
  author = {{MW SysArc}},
  title = {Newton's Law of Cooling Calculator},
  howpublished = {MW SysArc Tools},
  year = {2026},
  url = {https://math.mwsysarc.com/differential-equations/newton-cooling},
  note = {Published July 21, 2026; accessed August 31, 2026}
}

RIS

TY  - ELEC
AU  - MW SysArc
TI  - Newton's Law of Cooling Calculator
T2  - MW SysArc Tools
PY  - 2026
DA  - 2026-07-21
Y2  - 2026-08-31
UR  - https://math.mwsysarc.com/differential-equations/newton-cooling
N1  - Published July 21, 2026
ER  -

Clear answers

Frequently asked questions

What does the Newton cooling do?

Estimate an object's temperature as it approaches a constant ambient temperature.

How does the Newton cooling work?

The calculator applies T(t)=Tₐ+(T₀−Tₐ)e⁻ᵏᵗ. The temperature changes at a rate proportional to its difference from the surroundings, so that difference decays exponentially.

What can I learn from the Newton cooling?

It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.

Last reviewed . Calculations tested .

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