HomeCalculatorsMathNumerical CalculusSinc Function Calculator
Math calculator

Sinc Function Calculator

Unnormalized sinc(x)=sin(x)/x with sinc(0)=1. Same engine as Special Functions. Not normalized sinc. Not CAS. Runs locally.

Instant result
Result
—

Enter values to calculate.

Inputs—
Mode—
Formula—
Trust summary Engine tested · Specification checked · 58/58 tests · Production surface contract 4/4 · v1.10.0
Input interpretation
Enter values to calculate.
Result
—
Model
Unnormalized sinc(x)=sin(x)/x.
Scope
Unnormalized cardinal sine
Verification
Engine tested · 58/58 tests · Production surface contract 4/4 · Specification checked · v1.10.0
Named expert review
Optional · Not performed
Specification basis
  • ISO 80000-2:2019 Quantities and units — Mathematics
Specification basis
Evidence
13 golden · 8 boundary · 37 property · Production surface contract 4/4 · Artifact integrity PASS
Production
Embedded snapshot: unpublished · Build schema 1.10.0 ready · Semantic contract ✓ · Attestation report not published on origin · Live production status STALE (2 capabilities; 162 remain CURRENT) @ 2026-09-20T09:01:12.147Z
Semantic contract
PASS

Formulas

Core equations used by this calculator.

Definitionsinc(x) = sin(x)/x, sinc(0)=1
Zerossinc(kπ) = 0 for integer k ≠ 0
iSame engine as /special-functions. Not a second engine. Not /sinc. Normalized sinc is on /normalized-sinc.

How to use

1

Enter x

Any finite real. Default x=0 (removable singularity).

2

Read sinc(x)

sinc(0)=1. sinc(π)=0. sinc(π/2)=2/π.

Example calculations

Common configurations with formula and result.

ϟ

Removable singularity

x = 0

sinc(0) = 1
1
ϟ

sinc(π/2)

x = π/2

sinc(π/2) = 2/π
0.636619772368

Sinc Function calculator specification

Version 1.10.0 · Engine tested

Calculation status

Review policy · Evidence

Definition
The unnormalized sinc function is sinc(x)=sin(x)/x for x≠0, with the removable singularity sinc(0)=1. Even: sinc(−x)=sinc(x). sinc(π)=0. sinc(π/2)=2/π. This page is mode=sinc on math.special. Not sin(πx)/(πx). Not CAS.
What it calculates
Unnormalized sinc(x)=sin(x)/x.
Inputs
  • x
Outputs
  • value
Formula
sinc(x) = sin(x)/x, sinc(0)=1
Assumptions
  • Unnormalized cardinal sine
  • sinc(0)=1 by continuity
  • Not normalized sinc — that is /normalized-sinc
  • Not CAS
Units
  • dimensionless
Boundary conditions
  • non-finite x → INVALID_NUMBER
  • unknown mode (CAS) → INVALID_MODE
Example
x=0 → 1
Validation cases

2 published on this page · 58/58 tests · Production surface contract 4/4 · View evidence

  • x=0 → 1
  • x=π → 0
Specification basis
  • ISO 80000-2:2019 Quantities and units — Mathematics
Calculation version
1.10.0

Other calculators in this family: Bessel I Calculator, Bessel J Calculator, Bessel K Calculator, Bessel Y Calculator, Beta Function Calculator, Brent Method Calculator, Definite Integral Calculator, DFT Calculator . Explore all Numerical Calculus.

→ Bessel I Calculator I_n(x) for integer n=0…8. Same engine as Special Functions. Not W_{-1}. Not CAS. Runs locally. › → Bessel J Calculator J_n(x) for integer n=0…8. Same engine as Special Functions. Not W_{-1}. Not CAS. Runs locally. › → Bessel K Calculator K_n(x) for integer n=0…8 and x>0. Same engine as Special Functions. Not W_{-1}. Not CAS. Runs locally. › → Bessel Y Calculator Y_n(x) for integer n=0…8 and x>0. Same engine as Special Functions. Not W_{-1}. Not CAS. Runs locally. › → Beta Function Calculator Complete Euler B(x, y) = Γ(x)Γ(y)/Γ(x+y) for x>0, y>0. Same engine as Special Functions. Not incomplete beta. Not CAS. Runs locally. › → Brent Method Calculator Brent’s method (golden section plus inverse parabolic interpolation) for a minimum of a polynomial, sin, or exp on [a, b]. Same engine as One-Dimensional Optimization. Not root-finding Brent. Runs locally. › → Definite Integral Calculator Composite trapezoid, Simpson 1/3, or Gauss–Legendre of a polynomial, sin, or exp on [a, b]. Not indefinite symbolic integrate. Runs locally. › → DFT Calculator Forward DFT X[k]=Σ x[n] e^{−2πi kn/N}, N≤64, unnormalized. Same engine as Discrete Fourier Transform. Radix-2 FFT is on /fft. Not inverse, not Laplace. Runs locally. ›
}

Frequently asked questions

Key distinctions behind the calculation.

Is this a second special-functions engine?

No. It is mode=sinc on math.special, the same engine as /calc/math/special-functions.

Is this the normalized sinc used in DSP?

No. This seed is unnormalized sinc(x)=sin(x)/x, matching Wolfram Sinc. Normalized sin(πx)/(πx) is on /calc/math/normalized-sinc. Not CAS.

Where does this run?

Locally in the browser by default. REST and MCP call the same special-functions engine.