How to format and minify valid JSON safely
Reformat only insignificant whitespace in valid JSON, then verify strings, numbers, Unicode, escapes, and property-order assumptions.
jsonformattingminifyserializationvalidation
Guides
Understand causes, solutions, comparisons, and caveats, then try a related app right away.
Developer
The difference between JWT decoding and signature verification
Understand JWT headers, payloads, and signatures, why decoding does not establish validity, and how to inspect tokens safely.
jwtjwsauthenticationsecurityHow to encode special characters in URLs correctly
Learn to distinguish a full URL from a query value and safely encode spaces, plus signs, percent signs, and other special characters without double encoding.
urlpercent-encodingquery-parameterencodedecodeHow to encode Japanese and Unicode text with Base64
Avoid mojibake in Japanese text and emoji by converting strings to UTF-8 bytes before Base64 encoding.
base64unicodeutf-8encodingHow to choose JavaScript regular expression flags
Compare g, i, m, s, u, and y with concrete examples, then verify multiple matches, state, line handling, and Unicode behavior.
regexjavascriptflagsunicodepattern-testingHow to find and fix JSON syntax errors
Learn how to isolate and safely fix common JSON errors involving quotes, commas, keys, and numbers.
jsonsyntax-errordebuggingHow to test zero-width regular expression matches safely
Understand match positions and repeated execution for lookaheads, anchors, word boundaries, and other zero-width patterns.
regexzero-widthjavascript
Text
Why character counts differ between tools, and which count to match
The same text gets different character counts because tools count different units and treat spaces and line breaks differently. See where emoji, full-width text, and line breaks diverge, and how to match the count your destination uses.
character-countunicodeemojiwriting
Converters
How to convert binary, decimal, and hexadecimal numbers
Understand positional notation and manual conversion, then verify results while handling prefixes, invalid digits, negative values, and large integers.
binarydecimalhexadecimalradixnumber-conversionHow to distinguish Unix timestamp seconds from milliseconds
Learn how to identify Unix timestamps in seconds or milliseconds by combining digit count, source contracts, and converted results.
unix-timestampsecondsmillisecondsjavascriptIs a Unix timestamp UTC? Timestamps vs. time zones
A Unix timestamp counts from 1970-01-01 00:00:00 UTC and stores no time zone. See why one value shows different clock times and dates by zone and DST.
unix-timestamptimezoneutcdstWhat to check when converting between YAML and JSON
Understand how comments, types, anchors, and keys can be lost or change meaning during YAML and JSON conversion.
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