kb/data/developer.mozilla.org/en-US/docs/Glossary/Strict_mode-0.md

title	chunk	source	category	tags	date_saved	instance
Strict mode - Glossary | MDN	1/3	https://developer.mozilla.org/en-US/docs/Glossary/Strict_mode	reference	web, html, css, javascript, documentation	2026-05-05T05:46:08.501640+00:00	kb-cron

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1. Glossary
2. Strict mode

Strict mode

JavaScript's strict mode is a way to opt in to a restricted variant of JavaScript, thereby implicitly opting-out of "sloppy mode". Strict mode isn't just a subset: it intentionally has different semantics from normal code. Strict mode for an entire script is invoked by including the statement "use strict"; before any other statements.

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• See also

See also

• Strict mode
• Related glossary terms:
  • Sloppy mode