JSON Streaming & Partial Parser

Parse incomplete or streaming JSON — automatically completes truncated output from LLM APIs, streaming HTTP responses, and partial data chunks. See what was parsed and what was added to make it valid.

Partial / Incomplete JSON
Parsed Output

⚡ What gets fixed

  • Unclosed objects {"a": 1
  • Unclosed arrays [1, 2, 3
  • Truncated strings "hello wor
  • Missing commas between values
  • Trailing commas [1, 2,]
  • Partial key-value pairs {"key":
  • Multiple levels of unclosed nesting

🤖 LLM Use Cases

  • OpenAI / Claude streaming API responses
  • JSON output cut off by token limits
  • Structured output that didn't close cleanly
  • Real-time UI from streaming chunks
  • Debug incomplete LLM-generated JSON
  • Extract partial data before full response

🔧 How it works

  • Attempts native JSON.parse() first
  • Tracks open bracket/brace stack
  • Closes unclosed strings at truncation point
  • Adds missing closing brackets in order
  • Handles dangling keys with null values
  • Reports exactly what was added