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Online IDE · Workspaces · Interviews · Daily Challenges

Online IDE, cloud workspaces & coding interviews.

Codeground AI is the all-in-one developer platform. Spin up cloud workspaces, run code in 15+ languages, conduct secure technical interviews and use a complete developer toolbox — all from a single browser tab. No installs. No setup.

Free, no signup needed

Real Docker-isolated runtimes

Share any session with one link

main.pyREADME.md

1def greet(name): 2 return f"hi, {name}!" 3 4if name == "main": 5 print(greet("world"))|

$ python main.py

hi, world!

Engineers from world-class companies and universities use Codeground AI

Online IDE that just runs

A full Monaco-powered editor with syntax highlighting, autocomplete and one-click execution in 15+ languages. Hit Run, see output. That’s it.

Open the editor

Cloud Workspaces

Spin up persistent, container-isolated dev environments from a template or a Git repo. File tree, multi-tab editor, real terminal, live logs — pre-configured and ready to ship.

Launch a workspace

Interview Platform

Conduct fair, secure technical interviews with anti-cheat (tab tracking, focus, eye attention, copy-paste), live code collaboration, chat, timer and a structured evaluation report.

Create an interview

Ground Call

Host browser-based video calls built for pair programming and remote interviews. Start a room in one click, share the link, screen-share your editor, and switch between grid, spotlight, sidebar, or gallery layouts — no install required.

Start a call

Interactive Courses

System Design Dojo plus language tracks — sketch architectures for AI critique, or learn with guided lessons and runnable code in the browser.

Browse courses

Developer Toolbox

JSON Diff, JWT Debugger, Base64, Regex Tester, Epoch Converter, JSON ↔ CSV, QR generator and more — every micro-tool you Google, in one place.

Browse all tools

Dev Break Arcade

Quick browser games for when your brain needs a reset — snake, flappy, breakout, endless driving, and chess. No install, no account, just play and come back sharper.

Play a game

1

Pick a stack

Choose from 15+ language and database playgrounds. Your environment is provisioned in real Docker containers.

2

Code in the browser

A Monaco-powered editor with autocomplete, multi-file tabs, AI assistance and a real Linux terminal alongside it.

3

Run, share, ship

Hit Run for instant output. Share a link, invite collaborators, or take it to interview, evaluation or production.

Node.jsJavaScript runtimeJavaScript & Node.js — paste, run, share.→

PythonPython 3.xPython 3 online — paste, run, share.→

JavaJDK 11Java online compiler — javac + java in the browser.→

C++g++ / C++17C++ online with g++ — contests and quick compiles.→

Gogo 1.16+Go online — go run in the browser.→

Rustrustc 1.71Rust online — rustc in the browser.→

TypeScripttsc + NodeTypeScript online — tsc then Node.→

React (JSX)Live previewReact playground — imports, live preview.→

RubyRuby 3.xRuby online — run scripts in the browser.→

LuaLua 5.4Lua online — run scripts in the browser.→

GroovyJVM GroovyGroovy online — JVM scripts, no local JDK.→

Web (HTML/CSS/JS)Live previewHTML/CSS/JS editor — live preview.→

Shell / BashBash 5Bash online — Linux commands, no VM.→

MongoDBMongo shellMongoDB shell online — query without Atlas.→

PostgreSQLpsqlPostgreSQL online — SQL in the browser.→

MySQLmysqlMySQL online — SQL editor with a real server.→

Redisredis-cliRedis CLI online — no install.→

ClickHouseOLAP SQLClickHouse online — OLAP SQL playground.→

Cloud workspaces

A real dev environment, in a tab.

Launch a workspace from a template or import a Git repo. You get a multi-tab editor, a real terminal, dependency installs, persistent files and live runtime logs — already wired up.

Import any public Git repo or start from a template

Real Linux terminal with package managers and apt-style installs

Run servers and view live logs without leaving the workspace

Container-isolated, so no two workspaces collide

Persistent files — pick up where you left off, anywhere

workspace · my-api

app.tsroutes.ts

1import express from 'express'; 2const app = express(); 3app.get('/', (_, res) => 4 res.json({ ok: true })); 5app.listen(3000);

$ npm install && npm start

✓ deps installedlistening on :3000

interview · backend-engineer

REC

Candidate

1function twoSum(nums, target) { 2 const seen = new Map(); 3 for (let i = 0; i < nums.length; i++) { 4 const need = target - nums[i]; 5 if (seen.has(need)) return [seen.get(need), i]; 6 seen.set(nums[i], i); 7 } 8}

Interview platform

Run fair, secure technical interviews — without juggling four tabs.

A coding interview tool built by people who actually take coding interviews. Live editor, video, chat, timer and an evaluator-grade anti-cheat engine, all in one screen.

Tab-switch, focus and copy-paste detection

Eye-attention monitoring & full-screen enforcement

Multi-question sessions with structured rubrics

Live chat + collaborative editor + per-question timer

Auto-generated evaluation report you can export and share

Create an interview

AI Code SecurityScan snippets for secrets, SQLi, SSRF, and path traversal.

Commit Message GeneratorTurn a git diff into a Conventional Commits message.

Interview Question PackPaste a JD and get coding, behavioral, and design questions.

System Prompt DiffCompare two LLM system prompts for behavior and risk deltas.

Schema Seed DataGenerate realistic JSON fixtures from TS interfaces or SQL DDL.

GraphQL ExplainerExplain GraphQL queries and debug field / schema errors.

Text SummarizerCondense articles, notes, and docs into a clear summary.

AI Text GeneratorDraft blogs, emails, product copy, and outlines from a short brief.

JSON DiffCompare two JSON blobs and highlight what actually changed.

Diff & PatchGenerate clean unified diffs from text or source snippets.

JWT DebuggerDecode, verify and inspect JSON Web Tokens.

Base64 Encode / DecodeEncode and decode Base64 strings instantly, no install.

Epoch ConverterConvert Unix timestamps to and from human-readable dates.

Cron BuilderValidate cron expressions and preview upcoming run times.

Meeting PlannerSee the same meeting hour across every teammate’s timezone in one grid.

SQL FormatterPretty-print SQL and get an AI explanation before you ship the query.

ENV LinterCatch duplicate keys in .env files and redact values for safe sharing.

Date MathAdd weeks, business days, or months with proper timezone handling.

Log ParserColor severity levels and pretty-print embedded JSON log payloads.

Regex TesterTest, debug and explain regular expressions in real time.

JSON FormatterPretty-print, validate and minify JSON in one step.

JSON ↔ CSVConvert tabular data between JSON and CSV in both directions.

UUID GeneratorGenerate UUID v1/v4 in bulk, copy with one click.

QR GeneratorTurn URLs and text into shareable QR codes.

Password GeneratorStrong, configurable passwords without a roundtrip to the server.

Color PickerPick, convert and copy color values across HEX, RGB and HSL.

Speed TestMeasure your network throughput right from the browser.

Diagram StudioFlowcharts, architecture maps, and smart connectors.

Canvas DrawingA scratchpad canvas for whiteboarding and quick sketches.

Lucky Draw WheelSpin-the-wheel utility for raffles, picks and gamification.

Codeground AI at a glance

15+Languages & runtimes

0+Code executions to date

<2sMedian run time

100%Container-isolated

Yes. The core editor, runner, sharing and developer tools are free with no signup required. Sign up to unlock private grounds, persistent cloud workspaces, the daily challenges leaderboard and the interview platform.

Node.js, Python 3, Java, C++, Go, Rust, TypeScript, React (JSX), Ruby, Lua, Groovy, Bash, plus full HTML/CSS/JS with live preview, and database playgrounds for MongoDB, PostgreSQL, MySQL, Redis and ClickHouse — all running in real Docker-isolated containers.

Persistent, container-isolated dev environments you can launch from a template or a Git repository. They bundle a multi-tab editor, real terminal, dependency management and a live runtime — so you can ship without installing anything locally.

Create a session, share a link, and conduct a structured live coding interview with built-in anti-cheat: tab-switch detection, window-focus tracking, copy-paste logs, attention monitoring, full-screen enforcement and a complete activity log. Code, chat and timer all live in one screen, and a structured evaluation report is generated at the end.

All execution happens in sandboxed Docker containers. Your code is not permanently stored unless you explicitly save it. Authentication uses industry-standard JWT, and private projects support access controls.

Most programs return output in under 2 seconds. Codeground runs on optimised infrastructure with concurrent execution, so multiple users — and multiple workspaces — run independently and quickly.

Open a tab. Ship something today.

Start with Python, JavaScript, Rust or any of the 15+ runtimes. The editor is already warm.

Try today’s challenge