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dev-tool.org

100% Client-Side Privacy Guarantee (local · 0 B out)

A high-performance browser-native developer utilities platform.

JSON Formatter: Pretty-print, minification, key sorting

JWT Decoder: Header, payload & signature analysis

Regex Tester: Real-time expression evaluation with 5-color match highlights

Markdown Previewer: GFM tables and task list checkboxes

Sponsor Cards: Subtle developer sponsorship slots

Feature	Support	Execution Speed	Privacy
Client-Side Calculation	100%	< 4ms	0 B uploaded
Offline Functionality	Yes	Instant	Local Storage
Theme Customization	9 Themes	< 1ms	Sync

interface Config {
  privacy: "local · 0 B out";
  offline: true;
  themesCount: 9;
}

Built for developers by developers.

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Documentation & FAQs(Markdown preview guide)