encrypt
JWT Decoder: Expired Token and Signature Checks
Use a JWT decoder to inspect expired tokens, Base64URL payloads, claims, audience mismatches, and signature expectations without treating decode as verification.
Read noteKnowledge Base23 notes
Knowledge Base
Notes about data formats, browser-side utilities, API debugging, encoding boundaries, token inspection, metadata checks, and safe local workflows.
dev
Regex Tester for JavaScript Browser Bugs
Use a regex tester to debug JavaScript browser patterns, flags, escaping, lookbehind, Unicode classes, and production input mismatches before shipping code.
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Timestamp Converter for API Log Debugging
Use a timestamp converter to debug UTC time, local browser time, seconds versus milliseconds, API logs, database records, and timezone mismatches.
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Image Compressor: Reduce File Size Without Breaking Quality
Use an image compressor to reduce JPEG, PNG, and WebP file size while checking quality, dimensions, metadata, browser privacy, and when to switch to resizing or conversion.
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Password Generator: Entropy, Length, and Browser-Side Safety Checks
Use a password generator safely by checking entropy, length, character sets, browser-side randomness, clipboard risks, and when to use a password manager instead.
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Robots.txt Generator: Test Crawl Rules Before Blocking Search Engines
Use a robots.txt generator to draft User-agent, Disallow, Allow, and Sitemap rules, then test crawl behavior before blocking important pages from search engines.
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Barcode Online: Choose Code 128, EAN-13, or UPC-A Correctly
Learn how to choose the right barcode online before generating an image, including Code 128, EAN-13, UPC-A, Code 39, ITF-14, digit length rules, scanner expectations, and validation checks for labels or test data.
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Image Metadata Viewer Online: Check EXIF Before Sharing Photos
Use an image metadata viewer online to inspect EXIF, camera model, capture date, GPS coordinates, dimensions, software fields, and privacy-sensitive photo metadata before publishing, uploading, or sending images to clients.
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