Search & Knowledge

4 items

Google

General-purpose web search engine

Microsoft Bing

Microsoft's web search and discovery engine

Baidu

Chinese-language search and internet services platform

Wikipedia

Collaborative, multilingual online encyclopedia

AI Assistants

6 items

ChatGPT

OpenAI assistant for conversation, research, and creation

Gemini

Google's multimodal AI assistant

Claude

Anthropic's AI assistant for analysis and creation

Grok

AI assistant with real-time web and X access

DeepSeek

AI assistant and model platform by DeepSeek

Kimi

Moonshot AI assistant for coding and knowledge work

AI Platforms & Ecosystem

10 items

Google DeepMind

Google's AI research laboratory and model portfolio

Meta AI

Meta's AI products, models, and research

Microsoft AI

Microsoft's AI products, research, and business solutions

Hugging Face

Open-source hub for models, datasets, and AI applications

Arena

Community evaluation and leaderboards for AI models

Google AI Studio

Browser workspace for building with Gemini models

PyTorch

Open-source framework for machine learning and deep learning

Keras

High-level deep learning API for multiple backends

GPTZero

AI-generated text detection and authorship analysis

Not By AI

Badges for identifying human-created content

Cloud & Network

12 items

Cloudflare

Connectivity, security, and edge application platform

Amazon Web Services

Cloud computing platform by Amazon

Microsoft Azure

Cloud computing platform by Microsoft

GoDaddy

Domain registration, hosting, and website services

Namecheap

Domain registration, hosting, and web security services

NameSilo

Domain registration and portfolio management service

ExpressVPN

Commercial VPN service for encrypted network access

NordVPN

Commercial VPN service for privacy and secure access

Astrill VPN

Commercial VPN service with multi-protocol clients

RainYun

Chinese cloud hosting and infrastructure provider

Nexitally

Subscription service for multi-region network proxy access

TaiShan Net

Network proxy service focused on cross-region connectivity

Developer Tools

14 items

GitHub

Platform for Git repositories and collaborative development

GitHub Codespaces

Cloud development environments integrated with GitHub

StackBlitz

Browser-based IDE and instant web development environments

Visual Studio Code for the Web

Browser edition of Visual Studio Code

Sandpack

React toolkit for embeddable live code editors

Compiler Explorer

Interactive compiler explorer with assembly output

OnlineGDB

Browser-based Python editor and compiler

PyCharm

JetBrains IDE for Python development

Project Jupyter

Interactive notebooks and computing environment

cppreference

Reference for C, C++, and their standard libraries

Shields.io

Service for concise and consistent project badges

Tsinghua Open Source Mirror

Open-source software and Linux distribution mirror

Gitstar Ranking

Rankings of GitHub users, organizations, and repositories

committers.top

Rankings of active GitHub contributors by location

Web Development & Publishing

7 items

React

Library for web and native user interfaces

WordPress

Open-source publishing platform and content management system

Docusaurus

React-based static site generator for documentation

VitePress

Vite and Vue powered static site generator

VuePress

Vue-powered static site generator

Material for MkDocs

Material Design documentation theme for MkDocs

Hexo

Node.js framework for fast static blogs

Research & Publishing

5 items

arXiv

Open-access repository for scholarly preprints

Google Scholar

Search engine for scholarly literature

Nature

Multidisciplinary peer-reviewed science journal

Science

Multidisciplinary peer-reviewed journal from AAAS

Overleaf

Collaborative online LaTeX writing environment

Learning & Courses

5 items

MIT OpenCourseWare

Free course materials published by MIT

Coursera

Online courses, certificates, and degrees from institutions

edX

Online courses and credentials from universities and organizations

DeepLearning.AI

Courses and educational programs for artificial intelligence

Class Central

Search and review platform for online courses

Competitive Programming

14 items

Codeforces

Competitive programming contests, problems, and ratings

AtCoder

Online programming contests for all skill levels

Virtual Judge

Virtual judge aggregating problems from multiple platforms

Code Golf

Programming challenges focused on the shortest solutions

Big-O Algorithm Complexity Cheat Sheet

Reference for common data-structure and algorithm complexities

Luogu

Chinese competitive programming platform and problem archive

OI Wiki

Open knowledge base for competitive programming

OIerDb NG

Database of Chinese informatics competition participants

Original Problem Checker

Tool for checking whether a contest problem is original

Luogu Saver

Archive for preserved Luogu problems and solutions

Algorithm Duels Online

Team-based head-to-head contests using Codeforces problems

Solution Formatter

Formatter for Luogu solution articles and source code

CS Academy Diff Tool

Browser tool for comparing text outputs

CS Academy Graph Editor

Interactive editor for creating and exporting graphs

Mathematics & Computing

6 items

Wolfram|Alpha

Computational knowledge engine for mathematics and science

Desmos

Interactive graphing, geometry, and scientific calculators

GeoGebra

Interactive tools for geometry, algebra, and calculus

NumPy

Core Python library for numerical array computing

OEIS

Searchable encyclopedia of integer sequences

LaTeXLive

Online LaTeX formula editor with recognition and export

Design & Creation

11 items

Recraft

AI design platform for raster and vector image generation

QuiverAI

AI workspace for editable SVG creation and animation

OpenCut

Open-source browser-based video editor

Mult.dev

Tool for animated travel maps and route videos

CodeSnap

Editor for creating shareable code images

Colorable

Tool for checking and tuning color contrast

Skill Icons

Embeddable icons for programming languages and tools

BrandColors

Reference library of official brand color codes

Pixel Map Generator

Generator for pixel-style maps and multiple export formats

BentoGrids

Curated gallery of bento-style interface designs

MakerWorld

Community platform for 3D printing models

Tests & Benchmarks

8 items

Speedtest by Ookla

Internet connection speed measurement by Ookla

Net.Coffee

IP address, routing, and connectivity diagnostics

Password Monster

Browser tool for estimating password strength

volumeshader_bm

WebGL volumetric shader performance benchmark

HTML5 Fish Bowl

HTML5 graphics benchmark with animated fish

WebGL Aquarium

WebGL rendering benchmark with an animated aquarium

A Real Me

Collection of personality, ability, and knowledge tests

Political Orientation Test

Questionnaire for exploring political orientation

Media & Communities

5 items

YouTube

Video hosting, streaming, and creator platform

X

Real-time social network for public conversations

Facebook

Social network for people, groups, and organizations

Telegram Web

Browser client for Telegram messaging

bilibili

Chinese video platform and interest-based community

Browser Games

21 items

CrazyGames

Catalog of free browser games

FreeFocusGames

Browser games for attention and memory practice

.io Games

Directory of multiplayer .io browser games

Neal.fun

Collection of interactive web games and visual experiments

Lichess

Free and open-source online chess platform

generals.io

Multiplayer territory-control strategy game

florr.io

Multiplayer survival game built around flowers and petals

TileMan.io

Multiplayer territory-capture game

YORG.io

Supply-chain tower defense game against zombies

Bloxd.io

Multiplayer block-building and minigame platform

Wplace

Collaborative pixel canvas on a world map

sandspiel

Falling-sand simulation and creative sandbox

Kiomet

Multiplayer real-time territory strategy game

LINKR

Daily puzzle for connecting all points

diep.io

Multiplayer tank arena game

Gridspech

Rule-discovery puzzle with grids and symbols

The Evolution of Trust

Interactive game-theory explainer about trust

Tuxun

Photo-based geography guessing game

Guess Salt

Collection of daily, quiz, and multiplayer guessing games

Name Arena

Deterministic text battles generated from names

Board Game Collection

Collection of multiplayer digital board games

Software & Devices

6 items

Apple

Consumer technology products, services, and support

Apple Product Specs Hub

Reference for Apple device and chip specifications

SOCPK

Rankings and comparisons for mobile system-on-chip performance

Digital Lychee

Chinese storefront for licensed desktop and mobile software

Class Widgets 2

Next-generation open-source desktop timetable application

E-Classroom Terminator

Windows utility for inspecting and lifting classroom-computer restrictions

Online Services & Utilities

11 items

Google Translate

Translation service for text, documents, images, and websites

Polymarket

Prediction market based on tradable event contracts

Passport Index

Interactive passport rankings and visa-access reference

iLovePDF

Online toolkit for editing and converting PDF files

QR Code Generator

Customizable QR code creation and export tool

Forensically

Browser suite for digital image forensics

Note.ms

URL-addressed browser notes for quick sharing

Can You Speak Normally?

Decoder for Chinese initial-letter abbreviations

dazidazi

Online typing practice for Chinese, English, and code

WildAI

Third-party subscription service for international AI accounts

Luban SMS

Virtual number and SMS messaging service

Personal Projects

3 items

lailai's Tools

Privacy-friendly developer tools that run locally in the browser

lailai's Academy

Personalized self-study platform for high school students

lailai's Cloud

Personal file storage and resource hosting service