# 
[](https://www.npmjs.com/package/@thi.ng/router)
[](https://mastodon.thi.ng/@toxi)
> [!NOTE]
> This is one of 205 standalone projects, maintained as part
> of the [@thi.ng/umbrella](https://github.com/thi-ng/umbrella/) monorepo
> and anti-framework.
>
> 🚀 Please help me to work full-time on these projects by [sponsoring me on
> GitHub](https://github.com/sponsors/postspectacular). Thank you! ❤️
- [About](#about)
- [Status](#status)
- [Related packages](#related-packages)
- [Installation](#installation)
- [Dependencies](#dependencies)
- [Usage examples](#usage-examples)
- [API](#api)
- [Benchmarks](#benchmarks)
- [Authors](#authors)
- [License](#license)
## About
Generic trie-based router with support for wildcards, route param validation/coercion, auth.
- **Not bound to any environment**, usable on both client & server side
- Declarative route definitions, incl. [wildcards for matching rest
args](https://docs.thi.ng/umbrella/router/classes/Trie.html)
- Parametric routes, each param with optional value coercion & validation
- Route authentication handler to enable/disable routes based on other state
factors
- Fallback route redirect
- Enforced initial route (optional)
- Route formatting (with params & rest args)
- Optional HTML5 history & hash fragment support
## Status
**STABLE** - used in production
[Search or submit any issues for this package](https://github.com/thi-ng/umbrella/issues?q=%5Brouter%5D+in%3Atitle)
## Related packages
- [@thi.ng/hdom](https://github.com/thi-ng/umbrella/tree/develop/packages/hdom) - Lightweight vanilla ES6 UI component trees with customizable branch-local behaviors
- [@thi.ng/rdom](https://github.com/thi-ng/umbrella/tree/develop/packages/rdom) - Lightweight, reactive, VDOM-less UI/DOM components with async lifecycle and [@thi.ng/hiccup](https://github.com/thi-ng/umbrella/tree/develop/packages/hiccup) compatible
## Installation
```bash
yarn add @thi.ng/router
```
ESM import:
```ts
import * as rou from "@thi.ng/router";
```
Browser ESM import:
```html
```
[JSDelivr documentation](https://www.jsdelivr.com/)
Package sizes (brotli'd, pre-treeshake): ESM: 1.93 KB
## Dependencies
- [@thi.ng/api](https://github.com/thi-ng/umbrella/tree/develop/packages/api)
- [@thi.ng/checks](https://github.com/thi-ng/umbrella/tree/develop/packages/checks)
- [@thi.ng/equiv](https://github.com/thi-ng/umbrella/tree/develop/packages/equiv)
- [@thi.ng/errors](https://github.com/thi-ng/umbrella/tree/develop/packages/errors)
- [tslib](https://www.typescriptlang.org/)
Note: @thi.ng/api is in _most_ cases a type-only import (not used at runtime)
## Usage examples
Two projects in this repo's
[/examples](https://github.com/thi-ng/umbrella/tree/develop/examples)
directory are using this package:
| Screenshot | Description | Live demo | Source |
|:---------------------------------------------------------------------------------------------------------------------|:--------------------------------------------------------|:----------------------------------------------------|:---------------------------------------------------------------------------------|
| 
| Basic thi.ng/router usage with thi.ng/rdom components | [Demo](https://demo.thi.ng/umbrella/rdom-router/) | [Source](https://github.com/thi-ng/umbrella/tree/develop/examples/rdom-router) |
| 
| Complete mini SPA app w/ router & async content loading | [Demo](https://demo.thi.ng/umbrella/router-basics/) | [Source](https://github.com/thi-ng/umbrella/tree/develop/examples/router-basics) |
## API
[Generated API docs](https://docs.thi.ng/umbrella/router/)
```ts tangle:export/readme.ts
import {
HTMLRouter, HTMLRouterOpts, EVENT_ROUTE_CHANGED,
} from "@thi.ng/router";
import { isUUID } from "@thi.ng/checks";
// router configuration
const config: HTMLRouterOpts = {
// use hash fragment for routes
useFragment: true,
// fallback route (when no other matches)
default: "home",
// optional enforced route when router starts
initial: "home",
// Optional route path component separator. Default: `/`
separator: "/",
// Route prefix. Default: `/` (or `#/` if `useFragment` is enabled).
// All routes to be parsed by `route()` are assumed to have this prefix.
// All routes returned by `format()` will include this prefix.
prefix: "#/",
// actual route defs
// An array of route specs which route input strings will be matched against.
// Given routes will be pre-processed and stored in a Trie for fast matching.
// Additional routes can be dynamically added at a later time via .addRoutes()
routes: [
{
// each route MUST have an ID
id: "home",
// this array defines the route path items
match: "/home",
},
{
id: "user-profile",
// this rule is parametric
// variable items are prefixed with `?`
match: "/users/?id",
// coercion & validation handlers for "?id" param
// coercion fn is applied BEFORE validator
validate: {
id: {
coerce: (x) => parseInt(x),
check: (x) => x > 0 && x < 100,
},
},
},
{
id: "image",
// this route has 2 params and matches (for example):
// "/images/07a9d87b-c07a-42e3-82cf-baea2f94facc/xl"
match: "/images/?id/?size",
validate: {
id: {
check: (x) => isUUID(x),
},
size: {
check: (x) => /^(s|m|l|xl)$/.test(x),
},
},
},
{
id: "group-list",
// matches only: "/users" or "/images"
match: "/?type",
validate: {
type: {
check: (x) => /^(users|images)$/.test(x),
},
},
},
],
};
// `HTMLRouter` ONLY works in browser environments
// for non-browser use cases use `Router`
const router = new HTMLRouter(config);
router.addListener(EVENT_ROUTE_CHANGED, console.log);
router.start();
```
## Benchmarks
The below benchmarks are ported from
[router-benchmark](https://github.com/delvedor/router-benchmark), showing
**highly competitive** results for this package. The
[benchmark](https://github.com/thi-ng/umbrella/blob/develop/packages/router/bench/index.ts)
itself can be run from the repo root like so:
```bash
bun packages/router/bench/index.ts
```
```text
benchmarking: short static
warmup... 133.48ms (0.1 runs)
total: 113.79ms, runs: 1 (@ 1 calls/iter)
freq: 8788202.11 ops/sec
benchmarking: static with same radix
warmup... 166.98ms (0.1 runs)
total: 161.89ms, runs: 1 (@ 1 calls/iter)
freq: 6176873.20 ops/sec
benchmarking: dynamic route
warmup... 378.30ms (0.1 runs)
total: 374.80ms, runs: 1 (@ 1 calls/iter)
freq: 2668082.83 ops/sec
benchmarking: mixed static dynamic
warmup... 344.19ms (0.1 runs)
total: 340.33ms, runs: 1 (@ 1 calls/iter)
freq: 2938310.18 ops/sec
benchmarking: long static
warmup... 326.61ms (0.1 runs)
total: 327.84ms, runs: 1 (@ 1 calls/iter)
freq: 3050259.51 ops/sec
benchmarking: wildcard
warmup... 207.84ms (0.1 runs)
total: 207.49ms, runs: 1 (@ 1 calls/iter)
freq: 4819484.22 ops/sec
benchmarking: all together
warmup... 1525.05ms (0.1 runs)
total: 1532.24ms, runs: 1 (@ 1 calls/iter)
freq: 652640.66 ops/sec
```
## Authors
- [Karsten Schmidt](https://thi.ng)
If this project contributes to an academic publication, please cite it as:
```bibtex
@misc{thing-router,
title = "@thi.ng/router",
author = "Karsten Schmidt",
note = "https://thi.ng/router",
year = 2014
}
```
## License
© 2014 - 2025 Karsten Schmidt // Apache License 2.0