diff --git a/src/output-pages-base-url.js b/src/output-pages-base-url.js
new file mode 100644
index 0000000..669ea0d
--- /dev/null
+++ b/src/output-pages-base-url.js
@@ -0,0 +1,10 @@
+const core = require('@actions/core')
+
+function outputPagesBaseUrl(siteUrl) {
+  core.setOutput('base_url', siteUrl.href)
+  core.setOutput('origin', siteUrl.origin)
+  core.setOutput('host', siteUrl.host)
+  core.setOutput('base_path', siteUrl.pathname)
+}
+
+module.exports = outputPagesBaseUrl
diff --git a/src/output-pages-base-url.test.js b/src/output-pages-base-url.test.js
new file mode 100644
index 0000000..3e7d328
--- /dev/null
+++ b/src/output-pages-base-url.test.js
@@ -0,0 +1,62 @@
+const core = require('@actions/core')
+
+const outputPagesBaseUrl = require('./output-pages-base-url')
+
+describe('outputPagesBaseUrl', () => {
+  beforeEach(() => {
+    jest.restoreAllMocks()
+
+    jest.spyOn(core, 'setOutput').mockImplementation((key, value) => {
+      key, value
+    })
+    jest.spyOn(core, 'setFailed').mockImplementation(param => param)
+
+    // Mock error/warning/info/debug
+    jest.spyOn(core, 'error').mockImplementation(jest.fn())
+    jest.spyOn(core, 'warning').mockImplementation(jest.fn())
+    jest.spyOn(core, 'info').mockImplementation(jest.fn())
+    jest.spyOn(core, 'debug').mockImplementation(jest.fn())
+  })
+
+  it('gets expected outputs for profile site', async () => {
+    const baseUrl = 'https://octocat.github.io/'
+
+    outputPagesBaseUrl(new URL(baseUrl))
+
+    expect(core.setOutput).toHaveBeenCalledWith('base_url', baseUrl)
+    expect(core.setOutput).toHaveBeenCalledWith(
+      'origin',
+      'https://octocat.github.io'
+    )
+    expect(core.setOutput).toHaveBeenCalledWith('host', 'octocat.github.io')
+    expect(core.setOutput).toHaveBeenCalledWith('base_path', '/')
+  })
+
+  it('gets expected outputs for project site', async () => {
+    const baseUrl = 'https://octocat.github.io/my-repo/'
+
+    outputPagesBaseUrl(new URL(baseUrl))
+
+    expect(core.setOutput).toHaveBeenCalledWith('base_url', baseUrl)
+    expect(core.setOutput).toHaveBeenCalledWith(
+      'origin',
+      'https://octocat.github.io'
+    )
+    expect(core.setOutput).toHaveBeenCalledWith('host', 'octocat.github.io')
+    expect(core.setOutput).toHaveBeenCalledWith('base_path', '/my-repo/')
+  })
+
+  it('gets expected outputs for site with custom domain name', async () => {
+    const baseUrl = 'https://www.example.com/'
+
+    outputPagesBaseUrl(new URL(baseUrl))
+
+    expect(core.setOutput).toHaveBeenCalledWith('base_url', baseUrl)
+    expect(core.setOutput).toHaveBeenCalledWith(
+      'origin',
+      'https://www.example.com'
+    )
+    expect(core.setOutput).toHaveBeenCalledWith('host', 'www.example.com')
+    expect(core.setOutput).toHaveBeenCalledWith('base_path', '/')
+  })
+})