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JSONL Gazelle
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JSONL Gazelle
Fast viewer / editor for JSONL files
# Developer Tools
Featured on : Oct 25. 2025
Featured on : Oct 25. 2025
What is JSONL Gazelle?
JSONL is the go-to format for LLM evals, datasets, and logs. JSONL Gazelle makes it easy to view and edit analyze these files in VS Code and Cursor.
Problem
Users manually view and edit JSONL files (used for LLM evals, datasets, and logs) in basic text editors or incompatible tools, leading to inefficient readability, navigation, and modification of structured data.
Solution
A VS Code and Cursor extension that enables users to quickly view, edit, and analyze JSONL files with syntax highlighting, search, bulk edits, and data visualization features.
Customers
Machine learning engineers, data scientists, and developers working with large language models (LLMs), AI/ML datasets, or application logs in JSONL format.
Unique Features
Seamless integration into popular code editors (VS Code/Cursor), real-time JSONL validation, and bulk editing capabilities tailored for AI/ML workflows.
User Comments
Simplifies debugging LLM eval logs
Saves hours on dataset preprocessing
Indispensable for JSONL-heavy projects
Lacks native JSONL support elsewhere
Lightweight and responsive
Traction
Launched 1 month ago on Product Hunt, featured in VS Code Marketplace with 5k+ installs, mentioned in 12+ AI/ML communities.
Market Size
The global data annotation tools market, crucial for AI/ML datasets (often stored in JSONL), is projected to reach $8.2 billion by 2030 (Grand View Research, 2023).