Cartogenesis

Procedural world-map generator

Open source, free to use

Build a world from the ground up.

Generate a world map from a seed. Shape its terrain, rivers, climate and borders, then choose a map style and export the result.

Free and open source · Your maps stay on your device

A generated world map in the Natural style: a northern continent with a mountain range along its spine, a river system draining to a ragged southern coast, lakes, offshore islands, and the coast of a second continent at the right.
A generated world in the Natural style, with mountain ranges, river systems, lakes and islands. Seed 718106 · 62% ocean · 14 tectonic plates

How a world is made

  1. The tectonic plates view of a peninsula: the continent's plate in pale blue over the shaded relief, an ocean plate in pink to the west and another in yellow to the south-east, with a glowing seam where each meets the continent.
    01

    Plates and mountains

    Moving tectonic plates form mountain ranges, volcanic arcs and broad plateaus. Where plates pull apart, rift valleys can fill with water.

  2. The same peninsula in the elevation view: green lowlands and hills cut by valleys, darker ground along its steep south-east coast, and the sea floor in blues.
    02

    Erosion

    Erosion reshapes the terrain. Slopes collapse, rivers carve valleys, and sediment builds floodplains, fans and deltas.

  3. The same peninsula in the Natural style before its rivers: a pale band of shallow shelf water along every coast, and the deep blue sea beyond it.
    03

    Seas and ice

    Continental shelves lie along the coasts. Glaciers shape cold mountains, and ice sheets leave behind basins and lakes.

  4. The same peninsula in the biomes view: green forest along the coasts, yellow grassland across its dry middle, and paler country to the north.
    04

    Climate

    Seasons, ocean currents and terrain shape temperature and rainfall. Climate zones decide where forests, grasslands and deserts form.

  5. The same peninsula in the Natural style with its water: rivers running from the hills to both coasts, and a lake at the head of an inlet in the east.
    05

    Rivers and lakes

    Water flows downhill into rivers, lakes and seas. In dry inland basins, evaporation can shrink a lake and leave salt behind.

  6. The same peninsula in the political view: realms in flat tints of yellow, violet, blue and green over the relief, their borders following rivers and ridges.
    06

    Realms and peoples

    Geography shapes borders and settlement. Realms follow rivers, coasts and watersheds, while peoples spread into familiar terrain and across political borders.

Read the land

Five things the generator made on one stretch of coast. Each pin was placed by the generator itself, which found the place in the world's own data: where the plates meet, where the rain falls and where the rivers run.

The north coast of an island in the Natural style: a range of bare brown mountains along the shore with a lake among its peaks, green and olive country behind it with a wide river running north to a narrow arm of the sea, the coast of another land across that arm at the top right, and deep sea across the top.
  1. A coastal range An ocean plate sinks beneath the continent along this coast. Compression thickens and lifts the crust above it into a mountain range. On Earth: the Andes, above the Nazca plate.
  2. A rain shadow Moist sea air cools and drops its rain as it climbs the range. Beyond the crest, far less rain falls. On Earth: Patagonia, east of the Andes.
  3. A drowned valley A river cut this valley when the sea stood lower. The rising sea flooded it, leaving a long, narrow inlet. On Earth: Chesapeake Bay.
  4. A delta The river drops the sediment it carries as it enters the sea. Over time this builds low new land out from the coast. On Earth: the Mississippi delta.
  5. The continental shelf The continent continues beneath shallow water. At the shelf edge, usually 100 to 200 metres down, the sea floor steepens towards the deep ocean. On Earth: the North Sea.
One stretch of coast in the Natural style, with the five places the generator found on it. Seed 718106

Realistic map styles

Compare the same landscape in Atlas, Schoolroom and Natural.

  1. A corner of coast in the Atlas style, land tinted by height and climate: brown hills over a green coastal plain, rivers winding to the south and east coasts, and a blue sea deepening offshore.
    01

    Atlas

    Combines elevation and climate colours.

  2. The same coast in the Schoolroom style, land tinted by height alone: green lowlands rising to yellow and orange hills, blue rivers, and a pale blue sea with faint depth contours.
    02

    Schoolroom

    Shows elevation alone.

  3. The same coast in the Natural style, in satellite colours: olive and green lowlands under bare brown hills, rivers in pale blue, and a cobalt sea.
    03

    Natural

    Uses colours taken from satellite imagery.

The same region in Atlas, Schoolroom and Natural, at the same scale. Seed 718106

The data behind the map

The temperature, ocean currents, winds and rainfall calculated for the same coastline.

  1. A stretch of coast in the temperature view: the land in pale blues and whites, coldest blue in the north-west, warming to orange along the shore, and the sea a flat warm orange.
    01

    Temperature

    The mean annual temperature, in degrees Celsius.

  2. The same coast in the ocean currents view: the land a dark ground, and rows of small pale arrows over the sea running east along the coast.
    02

    Ocean currents

    The surface flow, coloured warm or cold against its latitude.

  3. The same coast in the winds view: large arrows, blue ones blowing to the south-east over the north of the land and the open sea, and orange ones blowing to the south-west along the coast.
    03

    Winds

    The prevailing wind through the year.

  4. The same coast in the rainfall view: the land shaded from pale yellow where it is dry in the north to green and deep blue where it is wettest along the shore, and the sea dark.
    04

    Rainfall

    The annual rainfall, from dry to wet.

Four views of the same coastline: its temperature, currents, winds and rainfall. Seed 718106

More map styles and data views are in the generator.

Features

Views
Fifteen views, including political borders, peoples, elevation, biomes, seasonal temperature and rainfall, tectonic plates, ocean currents and winds.
Styles
Twelve map styles, including Atlas, Vellum, Ink wash, Nautical, Pen and ink, Mars, Natural and a colour-blind-safe palette.
Themes
Seventeen interface themes, including light, dark, high contrast and colour-blind options.
Editing
Edit generated names and borders. Your changes are saved with the world.
Saves
Save a world and reopen the same file in the browser or the desktop app. In Chrome and Edge the browser's library can live in a folder on your computer, including one a sync service keeps in step.
Export
Export map images as PNG, WebP or JPEG, drawn at the world's true shape, or the data behind the map, one sample per cell: a 16-bit heightmap with its metre scale, and biome and realm index maps with their legends. Worlds up to 4096 × 4096 in the browser and on the desktop, whose map image is 8192 × 4096; phones are capped at 2048 × 2048.
Resolution
Choose the world's resolution. Higher settings add detail and need more memory; the browser starts at 512, the desktop app at 1024.
Acceleration
Optional graphics acceleration speeds up erosion and export rendering: WebGPU in the browser, OpenGL on the desktop.

Notes

Running it in a browser

Use a recent Chrome, Edge, Firefox or Safari. The first visit downloads the generator, about 4.6 MB, and caches it; nothing you make is uploaded anywhere.

Saved worlds stay in the browser's own storage, or, in Chrome and Edge, in a folder on your computer that you choose in the Library. The desktop app opens the same files.

Optional graphics acceleration uses WebGPU where the browser offers it.

Sizes, formats and speed

An export regenerates the world at the size you ask for, so the detail is real rather than enlarged. The map image is drawn at the world's true shape, twice as wide as it is tall: a 2048 world is a 4096 × 2048 picture. Larger worlds take longer and use more memory. On phones, browser exports are capped at a 2048 world, a 4096 × 2048 picture, to keep memory in bounds.

PNG keeps every pixel. WebP is smaller and softens thin rivers and borders slightly.

The Atlas is a work in progress

Today the Atlas lists a world's realms and landmarks and lets you rename them and place labels. Your changes are saved with the world. A later release, planned for 5.0, adds named continents, seas, bays, straits and ranges, with labels set out the way a printed atlas sets them.

Desktop versionWindows · Linux

Generate larger worlds with a desktop app that uses every processor thread. Download and Installation below says what each platform offers and how to install it; the steps live there rather than here, so there is one copy of them to keep true.

Get the latest release ↗

Download and Installation

Choose a download for Windows or Linux, or run Cartogenesis in the browser.

Windows

Unzip the portable zip and run Cartogenesis.exe. Nothing is installed. Or choose the MSI installer. It is unsigned, so Windows shows a SmartScreen warning. If you trust the download, choose “More info”, then “Run anyway”.

Cartogenesis-<version>-windows-portable.zip · Cartogenesis-<version>.msi

LinuxDebian · Ubuntu

The apt repository is recommended. The three commands below fetch the signing key, add the source line and run apt install. Alternatively, install the .deb with apt, or unpack and run the portable tarball. Java is bundled, with nothing else to install. The open-source graphics stack (Mesa) was tested. The proprietary NVIDIA driver was not. Saved worlds live in ~/.cartogenesis/worlds.

sudo curl -fsSL https://cartogenesis.com/apt/key.asc -o /etc/apt/keyrings/cartogenesis.asc
echo "deb [signed-by=/etc/apt/keyrings/cartogenesis.asc] https://cartogenesis.com/apt stable main" | sudo tee /etc/apt/sources.list.d/cartogenesis.list
sudo apt update && sudo apt install cartogenesis

Cartogenesis-<version>-linux-amd64.deb · Cartogenesis-<version>-linux-portable.tar.gz

Browser

Run Cartogenesis at cartogenesis.com. Nothing is installed and nothing is uploaded. You can also host the web zip yourself over HTTPS.

Cartogenesis-<version>-web.zip

Get the latest release ↗

Every file above, for the current release, with the notes saying what changed in it.

What comes next

Planned releases and what each one brings. No dates: a release lands when its work is done.

3.0.0
The realism audit: the plates, the seas, the air and the water measured against Earth, and corrected where the measurement showed how.
3.1.0
Rainfall that holds up at larger map sizes, monsoon coasts, ice sheets with the shape and weight of ice, and softer woodland edges.
3.2.0Current
Erosion shaped by rain and vegetation, rivers that begin with the slope and the flow, and ice sheets without stripes down their flanks.
3.3
Waves that shape beaches, spits and barrier islands.
3.x
Saved worlds that keep opening after an update.
3.x
Wetter continental interiors, and cold currents that make coastal deserts.
3.x
Rivers that widen downstream, with meanders, braided reaches and marshes.
3.x
More control over how the map is drawn: relief exaggeration and the direction of the light, how small a lake is still shown, the strength of the climate colouring, line weight, and the graticule's spacing.
3.x
A topographic map style with contour lines.
3.x
Hydraulic erosion on the graphics card.
3.x
A choice of world width.
4.0
The world as a sphere: a globe to turn, and a choice of map projections for the whole-world map and for exports.
4.x
Faster generation on more desktop graphics cards.
4.x
Import a heightmap, from Wonderdraft or any greyscale image, as the terrain a world is generated from.
4.x
Choose the kind of world the generator starts from, and paint the land yourself: continents form where and as you draw them, coastlines stay where you put them subject to erosion, and the climate, rivers and everything else are still generated on top.
5.0
The atlas: named land and sea features, with labels arranged the way a printed map arranges them. Renaming places and moving labels already work and stay.
5.x
Estuaries, reefs and atolls.
6.0
Symbol packs placed on layers over the generated map.

Found something wrong? Report it with the seed and the generation resolution. Open an issue, or write to bugreport@cartogenesis.com. Help ▸ Report a bug… in the app fills the form in for you.

Have a feature in mind? Say so. Suggest a feature, or write to dev@cartogenesis.com.