What is JSON Lines?
JSON Lines is a text format in which each line is one complete, self-contained JSON value. Because records are newline-delimited, a file can be streamed and appended to without re-parsing what came before.
Primary sources
Specifications cited by the tools below whose own titles define JSON Lines.
3 tools that work with JSON Lines
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AI & LLM Tools3
Fine-Tuning Dataset ConverterConvert training data between the six common chat formats, and validate the result against the rules the upload endpoints enforce.JSONL ValidatorValidate JSON Lines line by line, check chat-format structure, and estimate what training on the file would cost.Prompt Template GeneratorWrite a prompt once with placeholders, paste rows of data, and get every filled prompt back with its token count and cost.
Related terms
Terms that appear alongside JSON Lines on the same tools.