diff --git a/source/re-nav/share/index.html b/source/re-nav/share/index.html
new file mode 100644
index 0000000..09256bd
--- /dev/null
+++ b/source/re-nav/share/index.html
@@ -0,0 +1,61 @@
+{% extends "source/includes/base.html" %}
+{% import "source/includes/macros.html" as macros %}
+
+{% set title = "Re-Nav ↩ Share" %}
+
+{% block head %}
+<link rel="stylesheet" href="/scss/re-nav/re-nav.scss">
+<link rel="stylesheet" href="/scss/re-nav/share.scss">
+{% endblock %}
+
+{% block body %}
+<header class="page-header">
+  <h1>
+    <img src="../../assets/re-nav.png" alt="Re-Nav Logo">
+    Re-Nav
+  </h1>
+</header>
+
+<main class="page-main">
+  <p class="subtitle">
+    Welcome to Re-Nav's share page!
+    <br />
+    Use the share button in Re-Nav's options page to create a link with your
+    redirect.
+  </p>
+
+  <div class="hidden-by-default redirect">
+    <p class="matcher-data">
+      <span class="matcher-type"></span>
+      {{-":"-}}
+      <span class="matcher-value"></span>
+    </p>
+    <p class="arrow">↓</p>
+    <p class="redirect-data">
+      <span class="redirect-type"></span>
+      {{-":"-}}
+      <span class="redirect-value"></span>
+    </p>
+  </div>
+
+  {#
+    This element will be shown by JS on page load, and if Re-Nav is installed,
+    it will be used as the root container for the import button.
+  #}
+  <div class="hidden-by-default re-nav-import">
+    <p>
+      With <a href="..">Re-Nav</a> installed, you'll see a button here to import
+      this redirect.
+    </p>
+  </div>
+</main>
+
+<footer class="page-footer">
+  &copy;
+  <a href="https://git.bauke.xyz/Holllo/re-nav">AGPL-3.0-or-later</a>
+  💖
+  <a href="mailto:helllo@holllo.org">helllo@holllo.org</a>
+</footer>
+
+<script src="../../ts/re-nav/share.ts" type="module"></script>
+{% endblock %}
diff --git a/source/scss/re-nav/share.scss b/source/scss/re-nav/share.scss
new file mode 100644
index 0000000..67e859e
--- /dev/null
+++ b/source/scss/re-nav/share.scss
@@ -0,0 +1,54 @@
+.page-main {
+  display: grid;
+  gap: var(--spacing-16);
+  grid-template-columns: repeat(1, 1fr);
+}
+
+.subtitle {
+  font-weight: bold;
+  text-align: center;
+}
+
+.redirect {
+  border: 1px solid var(--foreground-1);
+  display: grid;
+  gap: var(--spacing-08);
+  grid-template-columns: repeat(1, 1fr);
+  padding: var(--spacing-16);
+
+  .matcher-data,
+  .redirect-data {
+    background-color: var(--background-color);
+    color: var(--background-1);
+    padding: var(--spacing-16);
+    overflow: auto;
+    text-align: center;
+
+    span {
+      font-weight: bold;
+    }
+  }
+
+  .matcher-data {
+    --background-color: var(--da-3);
+  }
+
+  .redirect-data {
+    --background-color: var(--da-7);
+  }
+
+  .arrow {
+    font-weight: bold;
+    text-align: center;
+  }
+}
+
+.re-nav-import {
+  p {
+    text-align: center;
+  }
+}
+
+.hidden-by-default {
+  display: none;
+}
diff --git a/source/ts/re-nav/share.ts b/source/ts/re-nav/share.ts
new file mode 100644
index 0000000..356f5b5
--- /dev/null
+++ b/source/ts/re-nav/share.ts
@@ -0,0 +1,78 @@
+import {Base64} from 'js-base64';
+
+const fragmentPrefix = '#json=';
+
+const exampleRedirect: Redirect = {
+  matcherType: 'hostname',
+  matcherValue: 'example.com',
+  redirectType: 'hostname',
+  redirectValue: 'example.org',
+};
+
+function decodeBase64<T>(base64: string): T {
+  return JSON.parse(Base64.decode(base64)) as T;
+}
+
+function encodeBase64(source: any): string {
+  return Base64.encode(JSON.stringify(source), true);
+}
+
+window.addEventListener('DOMContentLoaded', () => {
+  window['Re-Nav'] = {
+    decodeBase64,
+    encodeBase64,
+    share,
+  };
+
+  console.log(
+    "Want to manually create a share link? Use the window['Re-Nav'].share",
+    'function, where redirect is an object with matcherType, matcherValue,',
+    'redirectType and redirectValue properties. Like this:',
+  );
+  console.log(JSON.stringify(exampleRedirect, undefined, 2));
+  console.log(window['Re-Nav'].share);
+
+  if (!location.hash.startsWith(fragmentPrefix)) {
+    return;
+  }
+
+  const decoded = decodeBase64<Redirect>(
+    location.hash.slice(fragmentPrefix.length),
+  );
+  for (const [key, value] of Object.entries(decoded)) {
+    insertText(key as keyof Redirect, value);
+  }
+
+  for (const element of document.querySelectorAll('.hidden-by-default')) {
+    element.classList.remove('hidden-by-default');
+  }
+
+  document.querySelector('.subtitle')!.textContent =
+    'Someone shared a redirect with you!';
+});
+
+function insertText(key: keyof Redirect, value: string): void {
+  const insert = (selector: string, text: string) => {
+    document.querySelector(selector)!.textContent = text;
+  };
+
+  // eslint-disable-next-line unicorn/prefer-switch
+  if (key === 'matcherType') {
+    insert('.matcher-type', value);
+  } else if (key === 'matcherValue') {
+    insert('.matcher-value', value);
+  } else if (key === 'redirectType') {
+    insert('.redirect-type', value);
+  } else if (key === 'redirectValue') {
+    insert('.redirect-value', value);
+  } else {
+    console.warn(`Unknown key: ${key as string}`);
+  }
+}
+
+function share(redirect: Redirect): string {
+  const encoded = encodeBase64(redirect);
+  const url = new URL(window.location.href);
+  url.hash = `${fragmentPrefix}${encoded}`;
+  return url.href;
+}
diff --git a/source/types.d.ts b/source/types.d.ts
index 15b1de9..2bf1e5a 100644
--- a/source/types.d.ts
+++ b/source/types.d.ts
@@ -13,6 +13,21 @@ declare global {
     readonly PROD: boolean;
     readonly VITE_BROWSER: 'chromium' | 'firefox';
   }
+
+  interface Window {
+    'Re-Nav': {
+      decodeBase64<T>(base64: string): T;
+      encodeBase64(source: any): string;
+      share(redirect: Redirect): string;
+    };
+  }
+
+  type Redirect = {
+    matcherType: string;
+    matcherValue: string;
+    redirectType: string;
+    redirectValue: string;
+  };
 }
 
 // Make TypeScript see this file as a module.
diff --git a/vite.config.ts b/vite.config.ts
index 58a396c..669df3f 100644
--- a/vite.config.ts
+++ b/vite.config.ts
@@ -19,6 +19,7 @@ export default defineConfig({
         home: path.join(sourceDir, 'index.html'),
         queue: path.join(sourceDir, 'queue/index.html'),
         're-nav': path.join(sourceDir, 're-nav/index.html'),
+        're-nav/share': path.join(sourceDir, 're-nav/share/index.html'),
       },
     },
     sourcemap: true,