diff --git a/mod.ts b/mod.ts
index 1b2259f..5e8862a 100644
--- a/mod.ts
+++ b/mod.ts
@@ -99,7 +99,7 @@ Deno.serve({ port: config.api.port }, async (req) => {
       if (userNameMatches.length === 0) {
         if (body.name.length < 4 || body.name.length > 20)
           return genericResponse(STATUS_CODE.BadRequest, `Name too ${body.name.length < 4 ? 'short' : 'long'}.`);
-        if (body.pin.length < 4 || body.pin.length > 20) return genericResponse(STATUS_CODE.BadRequest, `PIN too ${body.pin.length < 4 ? 'short' : 'long'}.`);
+        if (body.pin.length < 4 || body.pin.length > 16) return genericResponse(STATUS_CODE.BadRequest, `PIN too ${body.pin.length < 4 ? 'short' : 'long'}.`);
         if (body.email.length > 255) return genericResponse(STATUS_CODE.BadRequest, 'Email too long.');
 
         const id = nanoid();