← Blogby Marcell Almeida

How to extract JSON from LLM output

Paste raw LLM output — get parsed JSON from code fences or inline objects.

Models wrap JSON in markdown fences, add preamble text, or truncate mid-object. The LLM JSON Extractor finds and parses JSON from messy chat completions.

Try it — paste LLM response text

Open full tool →

How it works

  1. Paste output — full model response including markdown.
  2. Auto-detect — fenced blocks and inline objects found.
  3. Copy JSON — validated, formatted result.

Common patterns

Handles ```json fences, bare objects, and arrays embedded in explanatory text. Multiple JSON blocks may appear — the tool picks the best match.

Validate after extract

Run extracted JSON through the JSON Formatter or JSON Schema Validator before production use.

The How to extract JSON from LLM output is free, runs locally, and never sends your data to a server. More developer tools at maratool.com.