3STF Tools
3STF Tools is a collection of over 100 fast, private, and free client-side utilities designed for developers, writers, and creators. Everything runs entirely within the browser, ensuring that user data, text, and inputs are never uploaded, tracked, or stored on external servers. The suite includes text converters, formatters, generators, encoding utilities, and randomized data tools designed to work instantly without signups, ads, or paywalls.
Checked on Oct 19, 2026.
Alternative resources
A Box of Tools
A collection of client-side developer and utility tools that run entirely in the browser without sending files or data to any external server.
Nutilz
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ToolKit
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