> ## Documentation Index
> Fetch the complete documentation index at: https://docs.linkutm.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Short links

> How short codes work, when to customize them, and what makes one valid.

The short code is the path after your short domain: `go.acme.com/{shortCode}`. linkutm stores one mapping per code; clicks on the code redirect to your full UTM-tagged destination URL.

## When to use it

* Always - every link gets a short code, auto-generated or custom.
* When the slug appears in print, on a podcast read, or anywhere a human reads it aloud.
* Skip customization for ads - auto-generated codes are fine and prevent typos.

## How to set one

<Tabs>
  <Tab title="Auto-generated">
    Leave the **Custom slug** field empty when creating a link. linkutm generates a short code automatically.

    <Frame>
      <img src="https://mintcdn.com/utm-e577acb5/nHQFp_ZWa_EOApO0/images/autogeneratedshorlink.png?fit=max&auto=format&n=nHQFp_ZWa_EOApO0&q=85&s=61d0e626b8becdc5bde846ac06a5138f" alt="Create Link modal - Short Link field showing auto-generated slug" width="1919" height="955" data-path="images/autogeneratedshorlink.png" />
    </Frame>
  </Tab>

  <Tab title="Custom slug">
    Type your slug in the **Custom slug** field. Allowed: lowercase letters, numbers, hyphens. Keep it short - 3-15 chars reads best.

    <Frame>
      <img src="https://mintcdn.com/utm-e577acb5/_OFWyAVC_YtnhKc0/images/addlinkpanel.png?fit=max&auto=format&n=_OFWyAVC_YtnhKc0&q=85&s=524c43b72192d17a60099d7f57dc2fa5" alt="Create Link modal - Custom slug field with user-typed branded slug" width="1920" height="991" data-path="images/addlinkpanel.png" />
    </Frame>
  </Tab>
</Tabs>

## Real-world example

| Use case             | Slug strategy         | Example                |
| -------------------- | --------------------- | ---------------------- |
| Paid ads             | Auto-generated        | `go.acme.com/k7m2qpz`  |
| Email newsletter CTA | Auto or themed        | `go.acme.com/may-deal` |
| Podcast read         | Memorable, brand-tied | `go.acme.com/acme-pod` |
| QR on print          | Short, no ambiguity   | `go.acme.com/menu`     |

## Common mistakes

<AccordionGroup>
  <Accordion title="Reusing a slug">
    Short codes are globally unique across linkutm. If the system says *"already exists"*, pick another - even if no one in your workspace uses it.
  </Accordion>

  <Accordion title="Long descriptive slugs">
    `q2-2025-product-launch-google-ads` defeats the purpose. Aim for ≤15 characters.
  </Accordion>

  <Accordion title="Special characters">
    Only `a-z`, `0-9`, `-` allowed. Underscores, slashes, periods get rejected.
  </Accordion>
</AccordionGroup>

## Edge cases

<Note>
  **Renaming an existing slug.** Edit the link → change **Short code**. The old slug stops working immediately. All historical clicks remain attached to the link's analytics.
</Note>

<Note>
  **System paths.** Slugs that collide with system paths (`api`, `health`, `docs`, `favicon.ico`) won't resolve through the redirect. Avoid these as custom slugs.
</Note>

<Note>
  **Archived links.** Archiving a link does not stop it from redirecting. The link continues to work normally. Archive is for organization only.
</Note>

<Note>
  **Expired links.** Once the expiration date passes, the link redirects to the fallback URL if one is set. Without a fallback URL, visitors see an error page.
</Note>