<base>: The BASE Element
Last updated: 2026-10-13
<base>The BASE Element
Sets the default base URL or default target for all relative URLs; at most one per document, before any URL-bearing element.
| Category | Metadata |
|---|---|
| Content Model | Flow content |
| Allowed Parents | Any element that accepts flow content |
| Content Tag | Self-closing — no closing tag needed |
| Status | Standard |
📝 Syntax
<base href="https://example.com/">⚙️ Attributes
This element supports the global attributes plus the following:
| Attribute | Value | Description |
|---|---|---|
href | Base address for resolving relative URLs. | |
target | Default target window for links (e.g. _blank). |
▶ Example
Edit the code below and see the live result in the playground:
🌐 Browser Support
| Browser |  Chrome |
 Edge |
 Firefox |
 Safari |
 Opera |
|---|---|---|---|---|---|
| <base> | ✓ v1 | ✓ v12 | ✓ v1 | ✓ v1 | ✓ v1 |
| Supported in all major browsers | |||||
Tip： base is a void element; once set, all relative links resolve against it—use with care.
❓ FAQ
QWhat does the base tag do?
A
<base href='https://example.com/app/'> sets the base URL for every relative URL on the page — images, links, and form submissions all resolve against it. The target attribute can also unify link behavior (e.g. open all in new windows).QDoes base affect anchor links?
AYes — a classic trap:
<a href='#top'> on a page with base href resolves to base-address/#top instead of the current page, causing surprise navigation. With base set, write in-page anchors as full current-page URLs.QMust base be the first element in head?
AStrongly recommended:
<base> only affects URLs declared after it, so any relative resource declared earlier resolves against the wrong base. Making it the first element in head is the safe position.🏷️ Related Tags
💡 Related Cases
More case studies coming soon — check back later.
📚 Related Tutorials
