Engineering

DELTA Function in Excel

Tests whether two values are equal. Returns 1 if equal, 0 otherwise.

Syntax

  • =DELTA(number1, [number2])

Arguments

  • number1 (required): First number
  • number2 (optional): Second number (default 0)

Examples

  • =DELTA(5, 5) - Test equality - Result: 1
  • =DELTA(5, 4) - Test inequality - Result: 0

DELTA in technical sheets

  • Document units in adjacent cells — many engineering functions require exact unit strings.
  • Use [CONVERT](/functions/convert/) for unit changes before specialized formulas.
  • Validate inputs with [ISNUMBER](/functions/isnumber/) and range checks.

Common errors

  • Only works with numbers

Use cases

  • Equality testing
  • Engineering
  • Logic operations

Frequently asked questions

  • Why use DELTA instead of IF or = operator? DELTA returns numeric 1 or 0, which is useful in calculations. =DELTA(A1, B1)*C1 multiplies C1 by 1 if A1=B1, by 0 otherwise. It's cleaner than =IF(A1=B1, 1, 0)*C1 for engineering formulas.
  • How do I count matching pairs with DELTA? Use SUMPRODUCT: =SUMPRODUCT(DELTA(A1:A10, B1:B10)) counts how many pairs are equal. Each DELTA returns 1 for match, 0 for non-match, and SUMPRODUCT sums them.
  • What happens if I omit the second argument? DELTA compares to 0 by default. =DELTA(A1) returns 1 if A1 is 0, returns 0 otherwise. Useful for checking if values are zero: =SUMPRODUCT(DELTA(A1:A100)) counts zeros in range.

Editorial review

  • Reviewed by Excel.Directory Editorial Team. Updated May 2026.