Spoold is a free, privacy-first developer toolbox that automatically detects what you paste (JSON, HTML, JWT, curl, etc.) and suggests the right tool. No sign-up required.

Is Spoold free to use?

Yes, Spoold is completely free to use. All tools work client-side in your browser with no data sent to servers.

Is my data safe with Spoold?

Absolutely. All processing happens in your browser. We don't store or transmit your data. Shared links use client-side encryption.

What tools are available?

Spoold includes JSON formatter, JSON diff, HTML preview, JWT decoder, time converter, CSV viewer, URL inspector, QR code generator/scanner, regex tester, Markdown preview, and curl converter.

Can I use keyboard shortcuts?

Yes! Press Cmd/Ctrl+K to search, or use shortcuts like 'jj' for JSON, 'hh' for HTML, 'tt' for Time converter, and more.

Spoold

Paste. Detect. Do.

Blog & Tutorials

Learn how to use Spoold tools effectively. Tutorials, tips, and guides to help you work faster and smarter.

SQL & GraphQL Editor: Query Database and APIs

Write and test SQL queries and GraphQL operations with syntax highlighting. Perfect for database management, API testing, and data analysis.

January 8, 2026

5 min read

Tutorial

#SQL#GraphQL#Database#API

Go, Rust & Java Code Editor: Systems Programming Languages

Edit Go, Rust, and Java code with full syntax highlighting. Perfect for systems programming, backend development, and high-performance applications.

January 7, 2026

6 min read

Tutorial

#Go#Rust#Java#Systems Programming

Create Mermaid Diagrams: Flowcharts, Sequence Diagrams & More

Generate beautiful diagrams with Mermaid syntax. Create flowcharts, sequence diagrams, class diagrams, Gantt charts, and more. Free online diagram maker.

January 6, 2026

8 min read

Tutorial

#Mermaid#Diagrams#Flowchart#UML

Online Code Editor: Write Code in 40+ Programming Languages

Edit code in Python, JavaScript, TypeScript, Java, Go, Rust, and 35+ more languages with syntax highlighting, auto-formatting, and code execution. Free online IDE.

January 5, 2026

7 min read

Tutorial

#Code Editor#Programming#IDE

Python Code Editor Online: Write and Run Python in Your Browser

Edit and execute Python code directly in your browser. No installation required. Syntax highlighting, auto-formatting, and instant execution with our free Python editor.

January 4, 2026

5 min read

Tutorial

#Python#Code Editor#Programming

JavaScript & TypeScript Editor: Write Modern Web Code

Edit JavaScript and TypeScript code with full IntelliSense, syntax highlighting, and browser execution. Perfect for web development, API testing, and learning.

January 3, 2026

6 min read

Tutorial

#JavaScript#TypeScript#Web Development

How to Format JSON Like a Pro: Complete Guide

Master JSON formatting with our comprehensive guide. Learn best practices, common pitfalls, and how to use the JSON Formatter tool effectively.

January 2, 2026

5 min read

Tutorial

#JSON#Formatting#Developer Tools

How to Decode JWT Tokens Securely

Understand JWT tokens, decode them safely, and learn how to inspect claims, expiry, and signatures using our JWT Decoder tool.

January 1, 2026

4 min read

Security

#JWT#Security#Authentication

Convert curl Commands to JavaScript: fetch vs axios

Learn how to convert curl commands to JavaScript fetch or axios requests. Step-by-step guide with examples and best practices.

December 30, 2025

6 min read

Tutorial

#curl#JavaScript#API

Preview HTML Without a Server: Live Rendering Guide

Test your HTML, CSS, and JavaScript instantly with our HTML Preview tool. No server setup required, perfect for quick prototyping.

December 28, 2025

3 min read

Web Development

#HTML#CSS#Preview

CSV to JSON Conversion: Complete Guide

Convert CSV files to JSON effortlessly. Learn auto-delimiter detection, data transformation, and export options with our CSV Viewer tool.

December 25, 2025

5 min read

Data

#CSV#JSON#Data Conversion

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