Dmitri Pavlutin • 4/20/2021

Solving a Mystery Behavior of parseInt() in JavaScript

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This article investigates the puzzling result of parseInt(0.0000005) returning 5 in JavaScript. It details how parseInt() converts its argument to a string, revealing that very small numbers use exponential notation (e.g., '5e-7'), and parseInt() then parses only the leading digit. The post provides a clear technical explanation and recommends using Math.floor() for safe integer extraction.

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#JavaScript #Parseint #Type Conversion
Solving a Mystery Behavior of parseInt() in JavaScript

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