How to Use Import from URL in Deno: Simple Guide

In Deno, you can import modules directly from a URL using the import statement with the full URL string. This allows you to use remote code without installing packages locally, for example: import { serve } from "https://deno.land/std/http/server.ts";.

Syntax

Use the import statement followed by the module names in curly braces, then from and the full URL string in quotes. The URL must point to a valid JavaScript or TypeScript module.

• import: keyword to bring in code
• { module }: named exports you want to use
• from: keyword to specify source
• "URL": full web address of the module

typescript

import { serve } from "https://deno.land/std/http/server.ts";

Example

This example imports the serve function from Deno's standard library URL and starts a simple HTTP server that responds with "Hello from Deno!".

typescript

import { serve } from "https://deno.land/std/http/server.ts";

const server = serve({ port: 8000 });
console.log("Server running on http://localhost:8000/");

for await (const req of server) {
  req.respond({ body: "Hello from Deno!" });
}

Output

Server running on http://localhost:8000/

Common Pitfalls

1. Forgetting to use full URL: Deno requires the full URL including protocol (e.g., https://), not just a domain or path.
2. Using unsupported URLs: The URL must point to a valid module file, not a webpage.
3. Not having network permission: Deno runs with secure defaults, so you must allow network access with --allow-net when running scripts that import from URLs.
4. Caching issues: Deno caches remote modules locally; if you want to update, use deno cache --reload.

typescript

/* Wrong: Missing protocol */
// import { serve } from "deno.land/std/http/server.ts";

/* Right: Full URL with https */
import { serve } from "https://deno.land/std/http/server.ts";

Quick Reference

Concept	Description	Example
Import keyword	Brings in code from a module	import { serve } from "URL";
Full URL	Must include protocol and path	"https://deno.land/std/http/server.ts"
Network permission	Allow network access to fetch modules	deno run --allow-net script.ts
Cache reload	Force update cached modules	deno cache --reload script.ts

Key Takeaways

Always use the full URL with protocol when importing modules in Deno.

Run Deno scripts with --allow-net to enable network access for URL imports.

Deno caches remote modules locally; use --reload to refresh them.

Imported URLs must point to valid JavaScript or TypeScript modules.

Importing from URLs lets you use remote code without local installs.