Quick Tip #006—Adding a 404 Not Found Page to your Static Site
A 404: Not Found page is a pretty standard thing on the web. It’s particularly useful when someone shares a broken or mistyped link. You don’t need dynamic middleware to do this, it’s pretty easy to add to a statically generated site. There are a few options, depending on your web host:
But first let’s make our 404.html template:
---
title: Oops! Not Found
permalink: 404.html
---
<!doctype html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>{{ title }}</title>
  </head>
  <body>
    <h1>{{ title }}</h1>
    <p>This is where you should tell the user how to find their content. Maybe on the <a href="{{ "/" | url }}">home page?</a></p>
  </body>
</html>Eleventy will output this template to 404.html.
If you’re using GitHub Pages or Netlify, there is no step two! A 404.html file in your output directory is all you need.
Netlify even has lovely multi-language 404 page support too using Redirects.
.htaccess #
For other hosts, if you use .htaccess for configuration you can use ErrorDocument. Make sure your root directory matches here!
ErrorDocument 404 /404.html
With --serve #
If you're using Browsersync with Eleventy (with eleventy --serve), you can configure it to do the 404 routing by passing a callback in your config. Read more on the BrowserSyncConfig option, the Browsersync callbacks option, and how to provide a 404 using a Browsersync callback.
const fs = require("fs");
const NOT_FOUND_PATH = "_site/404.html";
module.exports = function(eleventyConfig) {
  eleventyConfig.setBrowserSyncConfig({
    callbacks: {
      ready: function(err, bs) {
        bs.addMiddleware("*", (req, res) => {
          if (!fs.existsSync(NOT_FOUND_PATH)) {
            throw new Error(`Expected a \`${NOT_FOUND_PATH}\` file but could not find one. Did you create a 404.html template?`);
          }
          const content_404 = fs.readFileSync(NOT_FOUND_PATH);
          // Add 404 http status code in request header.
          res.writeHead(404, { "Content-Type": "text/html; charset=UTF-8" });
          // Provides the 404 content without redirect.
          res.write(content_404);
          res.end();
        });
      }
    }
  });
};Thank you Cassey Lottman.
- All Quick Tips
- #001—Inline Minified CSS
- #002—Inline Minified JavaScript
- #003—Add Edit on GitHub Links to All Pages
- #004—Zero Maintenance Tag Pages for your Blog
- #005—Super Simple CSS Concatenation
- #006—Adding a 404 Not Found Page to your Static Site
- #007—Fetch GitHub Stargazers Count (and More) at Build Time
- #008—Trigger a Netlify Build Every Day with IFTTT
- #009—Cache Data Requests
- #010—Transform Global Data using an `eleventyComputed.js` Global Data File
