Characters ignored before param name in URL constructor

Tests which characters are ignored in a query parameter name using the URL constructor

Shazzer Master

Created Jun 24, 2026

Updated Sep 5, 2026

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CategoryURL Handling

VisibilityPublic

TypeJS

CharsetUTF-8

Template used:

if (new URL("https://example.com/query?"+String.fromCodePoint($[i])+"param1=value").searchParams.get("param1") === "value") log($[i])

Sample payloads

if (new URL("https://example.com/query?"+String.fromCodePoint(9)+"param1=value").searchParams.get("param1") === "value") alert(9)

if (new URL("https://example.com/query?"+String.fromCodePoint(10)+"param1=value").searchParams.get("param1") === "value") alert(10)

if (new URL("https://example.com/query?"+String.fromCodePoint(13)+"param1=value").searchParams.get("param1") === "value") alert(13)

if (new URL("https://example.com/query?"+String.fromCodePoint(38)+"param1=value").searchParams.get("param1") === "value") alert(38)