PEM Certificate Decoder: Read SSL Certificates and RSA Keys Like a Pro
Inspect certs and keys without leaving the browser.
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80 Published Guides
Developer Tools
Free developer tools that run in your browser: JSON, regex, encoders, UUIDs, cron, DNS, SSL, and CSS helpers. No accounts, no uploads.
Articles — Page 8
Password Strength, Honestly Measured: Entropy Beats Rules
Just how strong is that password?
Meta Tag Preview: See Your Google and Social Cards Before You Publish
Preview how your page appears in Google and social cards.
IP Address Lookup: What Your IP Reveals (and What It Does Not)
Analyze an IP address or CIDR range.
HTTP Headers Inspection: What Servers Tell You When You Ask
See the response headers any URL returns.
Color Contrast Checker: Pass Accessibility Without Guessing
Pick colors and verify WCAG contrast ratios.
DNS Lookup and Propagation Checker: See What the Internet Sees
Resolve DNS records for any host.
CSS Box Shadows That Look Expensive (And the Settings Behind Them)
Design CSS box shadows with live preview.
CSS Border Radius Without Guessing: Visualize It, Copy It, Ship It
Craft wobbly and organic border radii visually.
Cron Expressions Explained: Read Any Schedule in 60 Seconds
Decode any cron schedule into plain English.
Understanding Developer Tools: Concepts & Architecture
💡 Core Workflows
Every guide in Developer Tools is written from real-world development and security scenarios. Use these articles to eliminate repetitive scripts and establish robust internal standards.
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