diff --git a/src/middleware.ts b/src/middleware.ts
index 4bca5a6..110098d 100644
--- a/src/middleware.ts
+++ b/src/middleware.ts
@@ -79,6 +79,7 @@ const validateChallengeBody = (
 ) => {
   if (!env.DISABLE_CHALLENGES) {
     const { solution, nonce } = req.body
+
     if (!solution || !nonce) {
       return res.status(400).send({
         status: "ERROR",
@@ -86,7 +87,7 @@ const validateChallengeBody = (
       })
     }
 
-    if (!Number.isInteger(nonce)) {
+    if (!Number.isInteger(Number(nonce))) {
       return res.status(400).send({
         status: "ERROR",
         message: "'nonce' must be an integer",
diff --git a/src/pow.ts b/src/pow.ts
index 5e24d8a..58d5f33 100644
--- a/src/pow.ts
+++ b/src/pow.ts
@@ -112,13 +112,13 @@ export const getChallenge = async (
   } satisfies ChallengeState as ChallengeState
 }
 
-const getSolution = (challenge: string, nonce: number) =>
+const getSolution = (challenge: string, nonce: number | string) =>
   createHash("sha256").update(`${challenge}:${nonce}`).digest("hex")
 
 interface VerifySolutionArgs {
   challenge: string
   difficulty: number
-  nonce: number
+  nonce: number | string
   solution: string
 }
 export const verifySolution = ({