diff --git a/src/block/put.js b/src/block/put.js
index bf76c8bf2..ad61799f7 100644
--- a/src/block/put.js
+++ b/src/block/put.js
@@ -24,7 +24,7 @@ module.exports = configure(({ ky }) => {
 
     const searchParams = new URLSearchParams(options.searchParams)
     if (options.format) searchParams.set('format', options.format)
-    if (options.format) searchParams.set('mhtype', options.mhtype)
+    if (options.mhtype) searchParams.set('mhtype', options.mhtype)
     if (options.mhlen) searchParams.set('mhlen', options.mhlen)
     if (options.pin != null) searchParams.set('pin', options.pin)
     if (options.version != null) searchParams.set('version', options.version)