Free
Minifiers · Developer Utilities
Free online CSS minifier with API access.
minifycssoptimizer
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Minifiers · Developer Utilities
Free online CSS minifier with API access.
Learning & Reference · CSS Tools
Long-running CSS and frontend resource with guides and snippets.
Generators · CSS Tools
Visual editor for CSS easing curves.
Pipelines & ETL · Data & Analytics
Modern data orchestrator with strong typing, testing and lineage.
SQL Tools
Online SQL playground for testing and sharing queries across engines.
GUI Clients · Database
Open-source database manager for SQL and NoSQL with web and desktop apps.
Pipelines & ETL · Data & Analytics
Analytics engineering: SQL-based transformation workflows with tests.
Regex
Regex tester with railway diagram visualization for PCRE, Python and JS.
Models & LLM APIs · AI for Developers
AI research lab with strong open-weight reasoning models and API.
Communities · Documentation & Learning
Community where developers write articles and share knowledge.
References · Documentation & Learning
Fast, offline-capable API documentation browser combining 100+ references.
Cheatsheets · Documentation & Learning
Rico's cheatsheets: concise cheatsheets for dozens of tools and languages.
Agent & LLM Frameworks · AI for Developers
Open-source LLM app platform: agents, workflows and RAG (trending).
Markdown · PDF & Documents
Online Markdown editor with live preview and cloud sync.
NoSQL · Database
Modern Redis-compatible in-memory store built for multicore (trending).
Relational · Database
Fast in-process analytical (OLAP) SQL database, like SQLite for analytics.
Search Engines · Database
Distributed search and analytics engine built on Apache Lucene.
Logs & Metrics · Monitoring & Observability
Elasticsearch, Logstash and Kibana for log ingestion and search.
Time & Cron · Developer Utilities
Convert Unix timestamps to human dates and back.
Whiteboards & Diagrams · Design & Prototyping
Hand-drawn style virtual whiteboard, ideal for quick diagrams.
Practice & Challenges · Documentation & Learning
Free coding practice and mentoring in 70+ languages.
SQL Tools
Modern PostgreSQL EXPLAIN plan visualizer by Dalibo.
SQL Tools
Long-standing PostgreSQL EXPLAIN plan analyzer and visualizer.
CLI Tools · Development Environment
Explains any shell command by matching it to man page text.