gohugoio/hugo · error

failed to create baseURL from

Error message

failed to create baseURL from %q: %s

What it means

When setting server info per language, Hugo constructs a `urls.BaseURL` from the resolved base URL string via `urls.NewBaseURLFromString`. This wraps a parse failure for that URL; `%q` is the offending string and `%s` the parse error.

Solutions

1. Set a valid, absolute `baseURL` (e.g. `https://example.com/`) in `hugo.toml`.
2. URL-encode any special characters in the baseURL.
3. For multihost, verify every language's `baseURL` is individually valid.
4. Re-run `hugo server` after fixing; the value is re-parsed on startup.

Example fix

// before
baseURL = "my site.example"
// after
baseURL = "https://my-site.example/"

import "net/url"
func validateBaseURL(s string) error {
  if s == "" { return fmt.Errorf("empty baseURL") }
  u, err := url.Parse(s)
  if err != nil { return err }
  if u.Scheme == "" || u.Host == "" { return fmt.Errorf("baseURL must be absolute: %q", s) }
  return nil
}

null

null

When it happens

Trigger: Fires after `fixURL` produces a string that `NewBaseURLFromString` cannot accept — typically a baseURL with control characters, an unparseable scheme, or empty after massaging. Triggered for each language config entry during `setServerInfoInConfig`.

Common situations: A `baseURL` in `hugo.toml` containing spaces or non-ASCII without encoding; a `--baseURL` flag with a malformed value; a multihost setup where one language's `baseURL` is invalid.

Related errors

• cannot use --renderToMemory with --destination
• failed to split baseURL hostport
• --appendPort=false not supported when in multihost mode
• cardinalityThreshold threshold must be between 0 and 100
• expected a map, a slice with an even number of elements, or…

AI-assisted analysis of gohugoio/hugo@52c9bd7908 (2026-08-09). Data as JSON: /api/errors/463dd1403ded3723. Report an issue: GitHub.

Appendix: source

Thrown at commands/server.go:651

		panic("no server ports set")
	}
	return c.withConfE(func(conf *commonConfig) error {
		for i, language := range conf.configs.Languages {
			isMultihost := conf.configs.IsMultihost
			var serverPort int
			if isMultihost {
				serverPort = c.serverPorts[i].p
			} else {
				serverPort = c.serverPorts[0].p
			}
			langConfig := conf.configs.LanguageConfigMap[language.Lang]
			baseURLStr, err := c.fixURL(langConfig.BaseURL, c.r.baseURL, serverPort)
			if err != nil {
				return err
			}
			baseURL, err := urls.NewBaseURLFromString(baseURLStr)
			if err != nil {
				return fmt.Errorf("failed to create baseURL from %q: %s", baseURLStr, err)
			}

			baseURLLiveReload := baseURL
			if c.liveReloadPort != -1 {
				baseURLLiveReload, _ = baseURLLiveReload.WithPort(c.liveReloadPort)
			}
			langConfig.C.SetServerInfo(baseURL, baseURLLiveReload, c.serverInterface)

		}
		return nil
	})
}

func (c *serverCommand) getErrorWithContext() any {
	buildErr := c.errState.buildErr()
	if buildErr == nil {
		return nil
	}

View on GitHub (pinned to 52c9bd7908)