Best JavaScript Tools in 2025

A front end web development playground.

Key CodePen features:

Real-time Collaboration Immediate Visual Feedback Integrated Development Environment (IDE) Community-Driven

Flagsmith lets you manage feature flags and remote config across web, mobile and server side applications. Deliver true Continuous Integration. Get builds out faster. Control who has access to new features. We're Open Source.

Key Flagsmith features:

Feature Flags Remote Config A/B/X Testing & Optimization Organization Management

Try for free Open Source freemium

Test your JavaScript, CSS, HTML or CoffeeScript online with JSFiddle code editor.

Key JSFiddle features:

Easy Sharing and Collaboration Real-Time Editing Supports Multiple Frameworks Embed Feature

Online playground for React.

Key CodeSandbox features:

Ease of Use Instant Collaboration Pre-configured Environments Integrated Development

Open Source

The Spring Framework provides a comprehensive programming and configuration model for modern Java-based enterprise applications - on any kind of deployment platform.

Key Spring Framework features:

Comprehensive Ecosystem Inversion of Control (IoC) Container Aspect-Oriented Programming (AOP) Spring Boot

Open Source

An Open Source, full stack, web application framework for the JVM.

Key Grails features:

Rapid Development Groovy Language Integration Spring Boot Foundation Plugin Ecosystem

Open Source

Apache Struts is an open-source web application framework for developing Java EE web applications.

Key Apache Struts features:

Robust Framework MVC Architecture Extensive Documentation Rich Tag Library

JavaScript Spreadsheet.

Key Handsontable features:

User-Friendly Interface Feature-Rich Customization Performance

Open Source

Java Web Frameworks.

Key Eclipse RAP features:

Cross-Platform Support Single Codebase Rich User Interface Integration with Eclipse Ecosystem

Vaadin is a web application framework for Rich Internet Applications (RIA).

Key Vaadin Framework features:

Rich Set of Components Java-centric Development Strong Type Safety Seamless Integration with Java Ecosystem

Open Source

The best HTML5 datagrid in the world.

Key AG Grid features:

Highly Customizable Rich Feature Set Performance Wide Range of Integrations

Open Source

Find the performance impact of adding a npm package to your bundle.

Key BundlePhobia features:

Size Analysis Dependency Insight Speed Optimization Comparative Analysis

Spark helps you take your inbox under control. Instantly see what’s important and quickly clean up the rest. Spark for Teams allows you to create, discuss, and share email with your colleagues.

Key Spark Mail features:

Smart Inbox Collaborative Email Customization Unified Inbox

Open Source

Hibernate an open source Java persistence framework project.

Key Hibernate features:

Object-Relational Mapping Automatic Table Generation HQL (Hibernate Query Language) Caching

Open Source