Free online toolbox for developers

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About Oltool

Dennis · Full-Stack Developer

A full-stack developer focused on web engineering, applied cryptography, and developer productivity tooling. All tools and documentation on this site are written and maintained by the author based on official specifications (RFC, MDN, IETF).

contact@oltool.net

About This Site

Oltool (oltool.net) is a free online toolbox for developers and IT professionals. Since launching in June 2025, it has grown to 158 everyday utilities.

Categories include: cryptography, Base64 encoding, JSON/YAML conversion, regex testing, QR code generation, IPv4 subnet calculation, JWT parsing, timestamp conversion, text processing, math calculations, network diagnostics, and more.

Our Principles

  • Privacy-First: All tools run entirely in your browser — no data is ever uploaded to any server.
  • Free & Open: All tools are free forever. No registration, no installation required.
  • Developer-Friendly: Every tool is carefully designed for a clean, efficient experience.
  • Always Improving: We regularly add new tools and optimize existing ones.

Site Update History

  • 2026-09-12Shipped user-state and trust signals: local favorites & recent tools, per-tool input history (auto-skipped for sensitive tools), a site-wide Changelog, per-tool "last verified" dates, and an anonymous usage counter (count only, no identifiers or content collected).
  • 2026-09-07Added content-updated timestamps across tool and blog pages; published 10 original developer tutorials (JSON, regex, character encoding, time zones, ports, color conversion, text diff, JSON Schema, JSONPath, ULID, etc.).
  • 2026-09-06Bulk-enhanced tool page depth: added step-by-step guides, more use cases, FAQs, and authoritative references across all tools to meet minimum content standards.
  • 2026-08-31Added topic hub pages and more reference sheets, improving the site-wide internal linking structure.
  • 2026-08-10Added "related tools / related references / related topics" internal-link blocks on tool pages to strengthen the internal link graph and content discovery.
  • 2026-07-20Improved the site-wide sitemap and hreflang multilingual mapping, optimizing indexing and canonical signals for search engines.
  • 2026-07-10Published privacy policy, terms of service, and contact pages; added page-load performance optimizations.
  • 2026-07-01Added structured data (SoftwareApplication / BreadcrumbList / FAQPage) to tool pages to improve search rich-result appearance.
  • 2026-06-25Shipped dark mode, following system preference with manual toggle and consistent contrast across the site.
  • 2026-06-20Added bilingual (Chinese/English) UI; tool names, descriptions, and page copy switch by language with synced canonical and hreflang.
  • 2026-06-15Oltool launched with the first batch of 159 developer tools fully operational.
  • 2026-05-20Completed the core tool set and the browser-local execution architecture (no data uploaded to servers), establishing the privacy-first positioning.

Content Sources & Accuracy

Every tool's descriptions, usage examples, and FAQ are written by the site author from official specifications and hands-on development experience, with references to authoritative sources such as IETF RFCs, MDN Web Docs, and standards documentation. We do not scrape or auto-spin content; every explanation aims to be accurate and verifiable. If you spot an error, please email us and we will fix it promptly.

Correction Commitment

We take the accuracy of every article seriously. All technical content is grounded in official specifications and cites references so it can be verified. If you find any of the following, please reach out via contact@oltool.net:

  • Statements that conflict with authoritative material (RFC, MDN, IETF, or other standards);
  • Broken links, unreachable resources, or examples that fail in real usage;
  • Outdated content (e.g., updated specifications, deprecated functions, changed recommended practices).

Once we receive a report, we commit to:

  1. Verifying it within 5 business days (consulting authoritative sources when needed);
  2. Correcting confirmed errors promptly, and marking the revision in the page's "last updated" timestamp;
  3. Fixing related pages for consistency whenever the same issue affects multiple pages.

Every correction you share is what makes this site more accurate and trustworthy—and we are grateful for it.

Tech Stack

Built with modern web technologies:

  • Framework: Vue 3 + Nuxt 4 (SSR static generation)
  • Styling: CSS variables + responsive design, dark/light mode
  • i18n: Built-in bilingual support (Chinese/English)
  • Hosting: EdgeOne CDN global acceleration
  • License: GPL-3.0

Support This Site

Every tool here is free, needs no account, and carries no pop-up ads. If it saved you time, you can support ongoing maintenance:

Contact

Feel free to reach out with questions, suggestions, or collaboration inquiries: