About

Cryonel is a focused developer-tools and API troubleshooting platform maintained by Semih Buğra Sezer.

It brings together the small but frequently needed tools—JSON, JWT, YAML, CSV, OpenAPI, Base64, UUID, timestamps, regular expressions, and related API utilities—that backend developers, frontend developers, API engineers, and DevOps teams use while diagnosing real integration problems.

Why Cryonel exists

Developer data is often sensitive: API responses may contain customer records, JWTs may carry identity claims, and OpenAPI contracts can describe private systems. Cryonel's free tools therefore process input locally in the browser. Tool input is not uploaded to Cryonel, placed in analytics events, or added to URLs. The separate API Guard product uses a server only for features that inherently require accounts, scheduled monitoring, and notifications; those boundaries are documented on the Technical Transparency page.

How tools and guides are checked

Each tool page includes a working example, common failure cases, privacy behavior, related documentation, and links to the standards behind the format where applicable. Automated browser checks exercise the tool catalog, verify that free-tool input does not leave the page, and crawl the production sitemap for broken links, redirects, canonical errors, duplicate titles, and retired legacy content.

Troubleshooting guides are written for a specific observable failure. They explain how to reproduce it, distinguish nearby causes, inspect the relevant transport or parser evidence, and turn the fix into a regression check. Reference pages are based on primary specifications such as RFCs and the OpenAPI Specification instead of unsourced keyword summaries.

Corrections and scope

Cryonel stays within developer data, API engineering, authentication, and debugging. It does not publish general technology news, automated trend articles, or unrelated product reviews. If a guide is inaccurate, incomplete, or unclear, send the affected URL and a reproducible example through the contact page. Corrections are reviewed against the relevant standard and working tool behavior.

Contact

For questions, bug reports, or suggestions, see the Contact page.