LLM Json

TypeScript SDK for extracting and correcting JSON from LLM outputs

EmergingOpen SourceLow lock-in

Pricing

Free tier

Flat rate

Adoption

Cooling

License

Open Source

Data freshness

Aging · Jun 8, 2026

Overview

What is LLM Json?

A TypeScript SDK that helps developers extract and correct JSON data from the output of large language models, ensuring accurate and usable data extraction.

Key differentiator

The only TypeScript SDK specifically designed for extracting and correcting JSON from large language model outputs, ensuring precise and reliable data handling.

Capability profile

Capability Radar

Ease of StartEcosystemValueMaturityFlexibilityScale Ready

Honest assessment

Strengths & Weaknesses

↑ Strengths

Extracts and corrects JSON from LLM outputsmedium

Ensures accurate data extraction for further processingmedium

Built with TypeScript, offering strong typing supportmedium

↓ Weaknesses

Steep learning curve for non-TypeScript developershigh

The SDK is built with TypeScript, which may require familiarity with strong typing and advanced JavaScript concepts.

Limited language support beyond Englishmedium

The tool's effectiveness in extracting JSON from LLM outputs might be reduced when dealing with non-English text or specific regional formats.

Frequent breaking changes between versionshigh

Previous updates, such as the v0.1 to v0.2 migration, required significant code rewrites and adjustments in chain definitions.

Small community and slower issue resolutionmedium

The open-source nature of the project means that issues might take longer to resolve due to limited contributors and maintainers.

Fit analysis

Who is it for?

✓ Best for

TypeScript developers needing to extract and correct JSON from AI-generated text

Projects where the accuracy of extracted data is critical, such as in financial or medical applications

Teams working on integrating LLM outputs into TypeScript-based systems

✕ Not a fit for

Developers who are not using TypeScript or do not require JSON correction capabilities

Scenarios where real-time streaming and processing of raw text output from LLMs is more critical than structured data extraction

Cost structure

Pricing

Free Tier

Available

Open source — free to use

Starts at

$0

Model

Flat rate

Enterprise

None

Performance benchmarks

How Fast Is It?

Ecosystem

Relationships

Next step

Get Started with LLM Json

Step-by-step setup guide with code examples and common gotchas.

View Setup Guide →