All versions
Engineering
The Excel ERFC function returns the complementary error function, 1 minus ERF(x).
Quick answer:
=ERFC(1) // ~0.1573
Syntax
=ERFC(x)
| Argument | Description | |
|---|---|---|
x | Required | The value to evaluate the complementary error function at. |
How to use it
ERFC returns the complementary error function, 1 minus ERF(x).
=ERFC(1) // ~0.1573
The error function is the area under the normal curve; it underpins probability, diffusion, and signal-noise calculations. ERFC (complementary) keeps accuracy in the far tail where 1−ERF would lose digits.
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Live demo
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Result:
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Frequently asked questions
What does ERFC return?
Returns the complementary error function, 1 minus ERF(x).
Which Excel versions support it?
All modern versions.
Can I use it across a range to count?
Yes — SUM the 1/0 results to count matches or threshold crossings, like a lightweight COUNTIF.
Why might it return an error?
Non-numeric input returns #VALUE!; out-of-domain values return #NUM!.
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