Worldsmith

Free plan Web

What Worldsmith is

Worldsmith is a free, open-source browser app that generates fantasy world maps from a numeric seed and can also render real Earth. Its procedural terrain uses warped fractal noise to shape features such as ridged mountains, while elevation, moisture, and temperature determine biomes. Rivers use D8 flow accumulation to form drainage networks. Exports include PNG maps up to 5120 px, editable SVG maps up to 3840 px, JSON world data, and 8-bit or 16-bit heightmaps. The maker says heightmaps can be imported into Unity, Unreal Engine, Blender, and World Machine. Earth mode uses NOAA ETOPO1 elevation and bathymetry averaged to about 5 km per sample. The interface discloses synthesized terrain detail in Earth mode, and setting Detail to 0 disables it. The app runs client-side without an account, server, or dependencies. Its climate model omits monsoons, ocean currents, and mountain-specific rain shadows; drainage follows the visible grid, so river consistency may change when panning. The maker says Earth mode's heightmap is about 27 MB and decodes to a roughly 67 MB resident grid, which may challenge older phones. The project is listed as founded in 2026 and is licensed under MIT.

Who it suits

Worldsmith suits people creating fantasy maps from a chosen seed or rendering Earth, and those who want to export maps or heightmaps for other tools. Its heightmaps are listed as suitable for Unity, Unreal Engine, Blender, and World Machine.

What it does well

Generate fantasy maps from a numeric seed
Earth rendering uses NOAA ETOPO1 data
Exports PNG, editable SVG, JSON, and heightmaps
Client-side app requires no account, server, or dependencies

What to know first

Climate model omits monsoons and ocean currents
Rivers may shift in global consistency when panning
Earth heightmap may challenge older phones
Firefox and Safari are untested

Limits

There is no paid tier listed; the free and open-source app has no account requirement. Earth mode's heightmap is about 27 MB and decodes to a roughly 67 MB resident grid, which may challenge older phones.

Plans

Plan	Billed and limits	Price
Free	Free and open source under MIT license · no account, server or dependencies	Free

As github.com lists them, read 8 Oct 2026. The maker's own page has the final word.

Getting started

Open the Worldsmith GitHub website in a browser.
Choose a numeric seed for a generated fantasy map, or use Earth mode.
Adjust Detail to 0 in Earth mode to disable synthesized terrain detail.
Export a PNG, SVG, JSON world file, or heightmap for your workflow.

Verdict

Worldsmith offers seeded fantasy map generation and an Earth mode, with image, vector, data, and heightmap exports. Consider the climate and drainage limits, and the larger Earth-mode memory footprint on older phones.

Questions

Is Worldsmith free?

Yes. Its listed Free plan costs nothing, and it is free and open source under the MIT license.

Which platforms does it support?

The listed platform is web; it runs entirely client-side in a browser.

What can I export?

PNG maps up to 5120 px, editable SVG maps up to 3840 px, JSON world data, and 8-bit or 16-bit heightmaps.

Can I use its heightmaps in other tools?

The maker says they are suitable for import into Unity, Unreal Engine, Blender, and World Machine.

Does it require an account or server?

No. The maker says it runs client-side with no account, server, or dependencies.

What are the stated model limitations?

The climate model omits monsoons, ocean currents, and mountain-specific rain shadows. Drainage is solved on the visible grid, so rivers may not remain globally consistent when panning.

Facts from Worldsmith's own pages

Accessibility limitation: The maker says the rendered canvas cannot be made readable by assistive technology, though controls are keyboard-operable and labelled. · github.com, 8 Oct 2026
Browser verification: The maker says the project is verified on Chromium, while Firefox and Safari are untested. · github.com, 8 Oct 2026
Client-side operation: The maker says the app runs entirely client-side with no account, server or dependencies. · thedatawiz-dot.github.io, 8 Oct 2026
Climate limitation: The maker says its climate model does not account for monsoons, ocean currents or mountain-specific orographic rain shadows. · github.com, 8 Oct 2026
Data disclosure: The maker says synthesized terrain detail in Earth mode is disclosed in the interface and can be disabled by setting Detail to 0. · github.com, 8 Oct 2026
Earth data: Earth mode uses NOAA ETOPO1 elevation and bathymetry, box-averaged to about 5 km per sample. · github.com, 8 Oct 2026
Exports: It exports PNG maps up to 5120 px, editable SVG maps up to 3840 px, JSON world data, and 8-bit or 16-bit heightmaps. · github.com, 8 Oct 2026
Founded: 2026 · github.com, 28 Sept 2026
Hydrology limitation: The maker says drainage is solved on the visible grid, so rivers may not remain globally consistent when panning. · github.com, 8 Oct 2026
Integrations: The maker says heightmaps are suitable for import into Unity, Unreal Engine, Blender and World Machine. · thedatawiz-dot.github.io, 8 Oct 2026
Limits: The maker says the Earth heightmap is about 27 MB and decodes to a roughly 67 MB resident grid, which may challenge older phones. · github.com, 8 Oct 2026
Purpose: Worldsmith generates infinite fantasy world maps in a browser from a numeric seed and can also render real Earth. · thedatawiz-dot.github.io, 8 Oct 2026
Rivers: Rivers are computed using D8 flow accumulation so tributaries merge into drainage networks. · thedatawiz-dot.github.io, 8 Oct 2026
Security and network behavior: The maker says shipped files have no runtime dependencies or network primitives, and its smoke tests check that the page makes no external requests. · github.com, 8 Oct 2026
Terrain and climate: Generated terrain uses domain-warped fractal noise with ridged mountain ranges, and biomes are derived from elevation, moisture and temperature. · thedatawiz-dot.github.io, 8 Oct 2026

Where Worldsmith stands on Freedom251

Game Map Generators#17 of 27