diff --git a/arc721/utils/strings.js b/arc721/utils/strings.js
new file mode 100644
index 0000000..17a0612
--- /dev/null
+++ b/arc721/utils/strings.js
@@ -0,0 +1,57 @@
+const FIELD_MODULUS = 8444461749428370424248824938781546531375899335154063827935233455917409239040n;
+
+function stringToBigInt(input) {
+  const encoder = new TextEncoder();
+  const encodedBytes = encoder.encode(input);
+  encodedBytes.reverse();
+
+  let bigIntValue = BigInt(0);
+  for (let i = 0; i < encodedBytes.length; i++) {
+    const byteValue = BigInt(encodedBytes[i]);
+    const shiftedValue = byteValue << BigInt(8 * i);
+    bigIntValue = bigIntValue | shiftedValue;
+  }
+
+  return bigIntValue;
+}
+
+function bigIntToString(bigIntValue) {
+  const bytes = [];
+  let tempBigInt = bigIntValue;
+  while (tempBigInt > BigInt(0)) {
+    const byteValue = Number(tempBigInt & BigInt(255));
+    bytes.push(byteValue);
+    tempBigInt = tempBigInt >> BigInt(8);
+  }
+  bytes.reverse();
+  const decoder = new TextDecoder();
+  const asciiString = decoder.decode(Uint8Array.from(bytes));
+  return asciiString;
+}
+
+function stringToFields(input, numFieldElements = 4) {
+  const bigIntValue = stringToBigInt(input);
+  const fieldElements = [];
+  let remainingValue = bigIntValue;
+  for (let i = 0; i < numFieldElements; i++) {
+    const fieldElement = remainingValue % FIELD_MODULUS;
+    fieldElements.push(fieldElement);
+    remainingValue = remainingValue / FIELD_MODULUS;
+  }
+  if (remainingValue !== 0n) {
+    throw new Error("String is too big to be encoded.");
+  }
+  return fieldElements;
+}
+
+function fieldsToString(fields) {
+  let bigIntValue = BigInt(0);
+  let multiplier = BigInt(1);
+  for (const fieldElement of fields) {
+    bigIntValue += fieldElement * multiplier;
+    multiplier *= FIELD_MODULUS;
+  }
+  return bigIntToString(bigIntValue);
+}
+
+console.log(stringToFields("ANS"));