JSON Formatting and Validation
Choose between a formatter and a validator, then work through common syntax errors.
JSON syntax · Troubleshooting · Browser versus server processing
Read guideGuides
Choose a task, understand the result, and spot the limits before using a tool. These guides cover data, files, calculations, and web diagnostics.
Image Compression and Format Choice
Compare JPEG and WebP, understand the quality control, and avoid losing transparency.
Output format · Transparency · Quality settings
Read guideManaging PDF Pages
Choose the right PDF operation and avoid page-number mistakes before exporting.
Merge · Split · Extract · Reorder · Remove
Read guidePercentages and Percentage Change
Choose the right formula for a share or change, and read the result correctly.
Part of whole · Change formula · Percentage points
Read guideReading DNS Records
Understand what each supported record means and why answers can differ between resolvers.
Record types · TTL · Resolver cache
Read guideTLS, HTTPS, and What a Check Can Tell You
Separate connection protection, certificate validity, and the limits of a point-in-time probe.
HTTPS · TLS 1.2/1.3 · Certificate verification
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