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JSON formatting and validation

The errors that break JSON

JSON is defined by RFC 8259 and is stricter than the JavaScript object syntax it resembles. Common causes of invalid JSON include:

• Trailing commas: {"a": 1,} is invalid JSON.
• Single quotes: strings and property names must use double quotes.
• Unquoted keys: {a: 1} is a JavaScript object literal, not JSON.
• Comments: standard JSON has no // or /* */ comment syntax.
• Unsupported values: NaN, Infinity, and undefined are not JSON values.
• A leading BOM: a byte order mark copied from a file can cause JSON.parse to fail. Ordinary trailing whitespace and newlines are valid.

If you need comments or trailing commas, use a format designed for them, such as JSONC or JSON5. ToolRino intentionally validates standard JSON.

Pretty-print versus minify

Formatting adds two-space indentation and line breaks so the structure is easier to read. Minifying removes optional whitespace. Both represent the same parsed data, although parsing and serializing can affect duplicate property names and some number representations.

Use formatted output when inspecting a response or reviewing a configuration diff. Use minified output when a compact value is required. Keep very large identifiers as strings because JavaScript numbers can lose integer precision.

Base64 and URL encoding

What Base64 actually does

Base64 represents bytes using a restricted ASCII alphabet so they can travel through text-oriented systems. Every three bytes become four Base64 characters. Standard Base64 adds = padding when needed, making the encoded length a multiple of four. For larger inputs, the result is roughly 33% larger than the original bytes.

Base64 is not encryption. It has no key and provides no secrecy. ToolRino encodes and decodes UTF-8 text using standard Base64. It does not process arbitrary binary files, and its decoder expects the standard alphabet and correct padding.

URL-safe Base64 replaces + and / with - and_. This tool does not automatically translate that variant, so a URL-safe value must be converted to padded standard Base64 before decoding.

Percent-encoding and two different functions

Percent-encoding represents a character’s UTF-8 bytes with percent escapes. A space becomes%20, while & becomes %26.encodeURIComponent escapes URL separators such as /,?, &, =, and :, making it suitable for one parameter value. encodeURI preserves those structural characters so a complete URL remains recognizable.

ToolRino uses component encoding. Paste the individual value when you need to preserve the surrounding URL. It treats + literally when decoding; plus means a space only in form-encoded data, not in general percent-encoding.

Generating strong passwords

Why length matters

Random-password strength grows with both the number of possible characters and the length. With all four groups enabled, ToolRino uses an 85-character alphabet: 26 uppercase letters, 26 lowercase letters, 10 digits, and 23 symbols. The simplifiedlog₂(alphabet size) × length calculation gives about 6.41 bits per independently selected character.

This reasoning applies to random output. A memorable substitution such asP@ssw0rd! is predictable and has much less uncertainty than its character count suggests. Prefer a longer unique generated password when a site permits it.

Why the random source matters

The generator uses crypto.getRandomValues, the browser’s cryptographic random source, with rejection sampling to avoid selection bias. It does not useMath.random. The result exists in the browser tab and ToolRino keeps no password history, so save it in a trusted password manager before leaving the page.

Common developer-tool questions

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