Ruby errors
High-intent troubleshooting for parsing and validation errors in Ruby. Use the exact error message and fix the first real issue.
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Top tools (local-only)
- JSON Validator
- JSON Repair
- YAML Validator
- CSV Validator
- XML to JSON
- Base64 Encode/Decode
- URL Encode/Decode
- JWT Decoder
JSON parse / deserialize errors
Most issues are not “bad JSON” but wrong content (HTML), truncation, extra characters, invalid escapes, or encoding.
- JSON::ParserError: 765: unexpected token at '<html>'
- JSON::ParserError: 765: unexpected token at 'False'
- JSON::ParserError: 765: unexpected token at 'NaN'
- JSON::ParserError: 765: unexpected token at '}'
- JSON::ParserError: 783: unexpected token at ''
- JSON::ParserError: 783: unexpected token at 'Infinity'
- JSON::ParserError: 783: unexpected token at 'None'
- JSON::ParserError: 859: unexpected token at ','
- JSON::ParserError: 859: unexpected token at 'nullnull'
- JSON::ParserError: 859: unexpected token at 'True'
- JSON::ParserError: 859: unexpected token at 'undefined'
YAML parse errors
YAML is indentation-sensitive. Fix the first reported line/column, then validate again before converting.
- Psych::SyntaxError: did not find expected key while parsing a block mapping
- Psych::SyntaxError: found character that cannot start any token while scanning for the next token
- Psych::SyntaxError: mapping values are not allowed in this context
CSV parser errors
CSV issues are usually delimiter + quoting rules. Find the first broken row and fix it.
- CSV::MalformedCSVError: Any value after quoted field isn't allowed in line 1.
- CSV::MalformedCSVError: Illegal quoting in line 1.
- CSV::MalformedCSVError: Unclosed quoted field on line 1.
Encoding / token errors (Base64, URL, JWT)
Encoded strings may contain secrets. Decode locally and normalize Base64URL/percent-encoding safely.
Related hubs
FAQ (quick)
Start here: Errors hub (runs locally, no upload).
Can I fix Ruby errors without uploading my data? Yes. no-upload.ru tools run locally in your browser (NO UPLOAD). Start with Errors hub and keep samples redacted if you must share them.
What is the fastest safe workflow? Validate first, fix the smallest broken part, then validate again before converting/exporting. This prevents silent downstream issues.
Why does Ruby errors happen? Most issues come from copy/paste truncation, wrong encoding, non-strict syntax (comments/trailing commas), or a shape mismatch (array vs object).
Which tool should I start with for Ruby errors? Start with Errors hub. If you still see errors, follow the related playbook/trend report on this page.