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Full width at half maximum

Concept in statistics and wave theory

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Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionSep 19, 2026
Entity authoritySource title only
Source-derived summary

In a distribution, full width at half maximum (FWHM) is the difference between the two values of the independent variable at which the dependent variable is equal to half of its maximum value. In other words, it is the width of a spectrum curve measured between those points on the y-axis which are half the maximum amplitude.

Half width at half maximum (HWHM) is half of the FWHM if the function is symmetric.

The term full duration at half maximum (FDHM) is preferred when the independent variable is time.

Editorial summary

The public source identifies “Full width at half maximum” as concept in statistics and wave theory. This brief keeps that definition visible, then builds a research path around Full, width and half.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current 89-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. Its value is orientation rather than verdict, with Full, width and half providing the first useful test.
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A short description can identify a subject without explaining its stakes. For “Full width at half maximum”, the useful work is to connect “concept in statistics and wave theory” to the records capable of establishing context and consequence.

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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 19, 2026.

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Source & attribution

This entry incorporates text from “Full width at half maximum” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.