v1.1.0 · single file · offline-ready

IDLE CITY —
Ages of Growth

A single-file idle city-builder that grows from a Stone Age village into a Fusion Age world-city — you shape the city, it runs itself.

Play the game View on GitHub Download for Windows (.exe) Download for Android (.apk)

Free & fully offline — nothing to install. The Android .apk is sideload-only (allow installs from unknown sources).

Population

2,500+

citizens to reach Ascension

Production

8.0×

income multiplier at the Fusion Age

Prestige

+25%

Legacy bonus carried per ascension

Industrial Age

Live on canvas

The progression

Eight ages, each one a bigger economy

Age 0

Stone

×1.0

Age 1

Bronze

×1.3

Age 2

Iron

×1.6

Age 3

Medieval

×2.0

Age 4

Industrial

×2.6

Age 5

Modern

×3.5

Age 6

Digital

×5.0

Age 7

Fusion

×8.0

Features

Everything a city needs, in one file

No frameworks, no libraries, no build step, no network. The whole game is one HTML page that renders a living city on a single canvas.

8 Ages of progress

Stone → Bronze → Iron → Medieval → Industrial → Modern → Digital → Fusion. Each age unlocks buildings, power, fuel and a bigger growth multiplier.

Tile city-builder

Lay roads, zone Residential / Corporate / Industrial / Fun districts, and place utilities, services, decor and world wonders on a procedural 44×28 map.

Living simulation

Zones self-construct, fill with citizens and level up on their own. Agents drive along your road network, with a day/night cycle and weather.

Real economy

Money, Materials, Food, Fuel, Power, Research and Happiness — all connected. Growth pauses the moment something runs short, and the status bar tells you exactly what.

Quests, tech & challenges

36 quests gate the ages, 10 research techs reshape the economy, and 3 timed challenges award medals for the fastest cities.

Events & disasters

Festivals, trade booms, migration waves, fires and earthquakes keep a run unpredictable — and citizens file petitions you can accept or refuse.

Full save system

3 save slots, an autosave every ~10 seconds, and a shareable export/import code to move a city between devices — all kept in your browser.

Ascension & Legacy

Reach the Fusion Age with 2,500+ citizens to Ascend — carrying a permanent Legacy bonus of +25% income into your next city.

Fully responsive & zero dependencies

A purpose-built mobile layout with touch pan and pinch-zoom down to 320 px wide — and not a single runtime library to load.

How it works

Four moves, endless cities

The city runs itself while you watch, plan and expand. Your job is to keep it sustainable — because if happiness ever hits zero, the run is over.

Lay roads

Paint roads outward from the Town Hall. Buildings only work when a road connects them back to it.

Zone the land

Residential houses citizens, Corporate gives jobs and income, Industrial makes materials, Fun raises happiness.

Watch the status bar

It always names what is blocking growth — no housing, no power, no fuel, unhappy citizens and more.

Advance the age

Complete the age's quests, press Advance Age, and unlock the next era — then Ascend at the Fusion Age.

Screenshots & demo

See the city grow

The same build you can play in your browser right now — nothing to install, nothing to sign up for.

Desktop view of IDLE CITY — Ages of Growth with the build panel, canvas map and side panel — **Desktop** — the full layout: build tabs, the 44×28 canvas map, and the side panel for quests, alerts and trends.

Mobile view of IDLE CITY — Ages of Growth with the responsive top bar and touch controls — **Mobile** — a purpose-built layout with touch pan and pinch-zoom down to 320 px.

The in-game tutorial card guiding the player through the first steps — **Tutorial** — six guided steps walk you through your first roads, zones and utilities.

The save and export dialog showing three slots and an export code — **Saves** — 3 slots, autosave, and a shareable export/import code.

Play the live demo

The full game, served from this repository's GitHub Pages — desktop or mobile, online or off.

Launch the game

Get started

Play in one click — or run it from source

There is no install step, no server and no internet connection required to play.

Just play it

Open the live demo — nothing to download.
Or download idle-city.min.html (minified) and double-click it.
Prefer readable code? index.html is the same game, un-minified.
Works offline in any modern browser, on desktop and mobile.

Run from source

# clone the repository
git clone https://github.com/drsamonline/idle-city-ages-of-growth.git
cd idle-city-ages-of-growth

# just open src/index.html, or serve it:
python3 -m http.server 8000

# rebuild the single-file bundles (dev only)
npm install
node build/build.js

Play needs nothing but a browser. Rebuilding the bundles needs Node.js 18+.

Zero dependencies Single HTML file Offline ready v1.1.0

FAQ

Questions, answered

How do I play it? Do I need to install anything?

No. Download idle-city.min.html (or index.html) and double-click it, or open the live demo. It runs in any modern browser, fully offline, with no installation, no server and no internet connection.

My buildings aren't working or nothing is growing.

Almost always roads. A building only functions when a road connects it back to the Town Hall. Read the status bar at the bottom — it names the exact blocker (no housing capacity, no power, fuel shortage, unemployed citizens).

Why did my city collapse?

Happiness reached zero — that's the game-over condition. Happiness falls with pollution, unemployment, power and fuel shortages, waste and bad weather, and rises with jobs, Fun districts, services and decor.

How do I advance to the next Age?

Complete all the quests for your current Age, then press Advance Age in the side panel. The button only lights up when the set is finished.

What is Ascension and Legacy?

Once you reach the Fusion Age with 2,500+ citizens, Ascend to start a brand-new city while keeping a permanent Legacy bonus of +25% income per ascension.

Does it work on my phone?

Yes — mobile is a first-class target. The layout adapts down to 320 px wide, the top bar wraps so the speed controls stay reachable, and you can drag to pan and pinch to zoom. Add it to your home screen for a full-screen, app-like experience.

Is my progress saved? Where?

Yes. There are 3 save slots plus an autosave every ~10 seconds. Saves live in your browser's own localStorage — nothing is sent anywhere. Use the Export code to back up a city or move it to another device.

Is it really one file with no dependencies?

Yes. No frameworks, no libraries at runtime, no external images, fonts or data, no analytics and no network calls. The dev tools (terser and html-minifier-terser) are only used to build the minified file and are never shipped.

Can I use or modify it in my own project?

It is released under the PolyForm Noncommercial License 1.0.0 — free for personal, hobby, study, teaching, research and other non-commercial use. Attribution is mandatory: credit Dr. Sohil Momin and link the original repository. Commercial use requires a separate paid licence. See the repository's LICENSE and ATTRIBUTION.md.

Something's broken or I have an idea. Where do I say so?

Open an issue on the repository. Please include your browser and OS, whether it's desktop or mobile, and what the status bar said.

PolyForm Noncommercial 1.0.0 v1.1.0 0 dependencies 8 ages