diff --git a/packages/circuits/tests/rsa.test.ts b/packages/circuits/tests/rsa.test.ts
index 907365fc6..8b7cb0ec1 100644
--- a/packages/circuits/tests/rsa.test.ts
+++ b/packages/circuits/tests/rsa.test.ts
@@ -6,6 +6,7 @@ import path from "path";
 import { DKIMVerificationResult } from "@zk-email/helpers/src/dkim";
 import { generateCircuitInputs } from "@zk-email/helpers/src/input-helpers";
 import { verifyDKIMSignature } from "@zk-email/helpers/src/dkim";
+import { toCircomBigIntBytes } from "@zk-email/helpers/src/binaryFormat";
 
 exports.p = Scalar.fromString(
   "21888242871839275222246405745257275088548364400416034343698204186575808495617"
@@ -33,7 +34,7 @@ describe("RSA", () => {
     dkimResult = await verifyDKIMSignature(rawEmail);
   });
 
-  it("should verify rsa signature correctly", async function () {
+  it("should verify 2048 bit rsa signature correctly", async function () {
     const emailVerifierInputs = generateCircuitInputs({
       rsaSignature: dkimResult.signature,
       rsaPublicKey: dkimResult.publicKey,
@@ -55,6 +56,29 @@ describe("RSA", () => {
     await circuit.assertOut(witness, {})
   });
 
+  it("should verify 1024 bit rsa signature correctly", async function () {
+    const signature = toCircomBigIntBytes(
+      BigInt(
+        102386562682221859025549328916727857389789009840935140645361501981959969535413501251999442013082353139290537518086128904993091119534674934202202277050635907008004079788691412782712147797487593510040249832242022835902734939817209358184800954336078838331094308355388211284440290335887813714894626653613586546719n
+      )
+    );
+
+    const pubkey = toCircomBigIntBytes(
+      BigInt(
+        106773687078109007595028366084970322147907086635176067918161636756354740353674098686965493426431314019237945536387044259034050617425729739578628872957481830432099721612688699974185290306098360072264136606623400336518126533605711223527682187548332314997606381158951535480830524587400401856271050333371205030999n
+      )
+    );
+
+    const witness = await circuit.calculateWitness({
+      signature: signature,
+      modulus: pubkey,
+      // TODO: generate this from the input
+      base_message: ["1156466847851242602709362303526378170", "191372789510123109308037416804949834", "7204", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0"],
+    });
+    await circuit.checkConstraints(witness);
+    await circuit.assertOut(witness, {});
+  });
+
   it("should fail when verifying with an incorrect signature", async function () {
     const emailVerifierInputs = generateCircuitInputs({
       rsaSignature: dkimResult.signature,