diff --git a/frontend/index.client.js b/frontend/index.client.js
index 0a14213..f5f24ae 100644
--- a/frontend/index.client.js
+++ b/frontend/index.client.js
@@ -68,7 +68,7 @@ window.addEventListener('DOMContentLoaded', () => {
   let customName = '', adminUrl = '', file = null
 
   const NAME_REGEX = /^[a-zA-Z0-9+_\-\[\]*$@,;]{3,}$/
-  const EXPIRE_REGEX = /^\d+\s*[mhdwM]?$/
+  const EXPIRE_REGEX = /^\d+\s*[smhdwM]?$/
   const submitButton = $('#submit-button')
   const deleteButton = $('#delete-button')
   const pasteEditArea = $('#paste-textarea')
diff --git a/src/common.js b/src/common.js
index c9cce6f..9f00ff9 100644
--- a/src/common.js
+++ b/src/common.js
@@ -75,7 +75,7 @@ export function parsePath(pathname) {
 }
 
 export function parseExpiration(expirationStr) {
-  const EXPIRE_REGEX = /^[\d\.]+\s*[mhdwM]?$/
+  const EXPIRE_REGEX = /^[\d\.]+\s*[smhdwM]?$/
   if (!EXPIRE_REGEX.test(expirationStr)) {
     throw new WorkerError(400, `‘${expirationStr}’ is not a valid expiration specification`)
   }
@@ -136,4 +136,4 @@ export function getDispFilename(fields) {
 
 export function isLegalUrl(url) {
   return URL.canParse(url)
-}
\ No newline at end of file
+}
diff --git a/src/index.js b/src/index.js
index b476f22..5f6f765 100644
--- a/src/index.js
+++ b/src/index.js
@@ -45,4 +45,3 @@ async function handleNormalRequest(request, env, ctx) {
     throw new WorkerError(405, "method not allowed")
   }
 }
-