diff --git a/js/payments/zapSplit.js b/js/payments/zapSplit.js
index a42ba18d..c2a304b9 100644
--- a/js/payments/zapSplit.js
+++ b/js/payments/zapSplit.js
@@ -23,8 +23,57 @@ const DEFAULT_DEPS = Object.freeze({
   platformAddress: Object.freeze({ getPlatformLightningAddress }),
 });
 
+function parsePercentValue(value) {
+  if (typeof value === "number") {
+    return Number.isFinite(value) ? value : NaN;
+  }
+
+  if (typeof value === "bigint") {
+    return Number(value);
+  }
+
+  if (typeof value === "string") {
+    const trimmed = value.trim();
+    if (!trimmed) {
+      return NaN;
+    }
+
+    if (trimmed.includes("/")) {
+      const [firstRaw, secondRaw] = trimmed.split("/").map((part) => part.trim());
+      if (firstRaw && secondRaw) {
+        const first = Number(firstRaw);
+        const second = Number(secondRaw);
+        if (Number.isFinite(first) && Number.isFinite(second) && first >= 0 && second >= 0) {
+          const total = first + second;
+          if (total > 0) {
+            return (second / total) * 100;
+          }
+        }
+      }
+    }
+
+    const percentStripped = trimmed.endsWith("%")
+      ? trimmed.slice(0, -1).trim()
+      : trimmed;
+    const directNumeric = Number(percentStripped);
+    if (Number.isFinite(directNumeric)) {
+      return directNumeric;
+    }
+
+    const match = percentStripped.match(/-?\d+(?:\.\d+)?/);
+    if (match) {
+      const fallback = Number(match[0]);
+      return Number.isFinite(fallback) ? fallback : NaN;
+    }
+
+    return NaN;
+  }
+
+  return Number.isFinite(value) ? Number(value) : NaN;
+}
+
 function getOverridePlatformFee() {
-  const override = globalThis?.__BITVID_PLATFORM_FEE_OVERRIDE__;
+  const override = parsePercentValue(globalThis?.__BITVID_PLATFORM_FEE_OVERRIDE__);
   if (Number.isFinite(override)) {
     return override;
   }
@@ -32,7 +81,7 @@ function getOverridePlatformFee() {
 }
 
 function clampPercent(value) {
-  const numeric = Number(value);
+  const numeric = parsePercentValue(value);
   if (!Number.isFinite(numeric)) {
     return 0;
   }
@@ -341,4 +390,6 @@ export const __TESTING__ = Object.freeze({
   determineRecipientPubkey,
   derivePointerTag,
   mergeDependencies,
+  parsePercentValue,
+  clampPercent,
 });
diff --git a/tests/zap-split.test.mjs b/tests/zap-split.test.mjs
index 22962299..b683ce2c 100644
--- a/tests/zap-split.test.mjs
+++ b/tests/zap-split.test.mjs
@@ -180,6 +180,42 @@ async function testSplitMath() {
   delete globalThis.__BITVID_PLATFORM_FEE_OVERRIDE__;
 }
 
+async function testStringFeeOverride() {
+  const videoEvent = {
+    id: "event-id",
+    pubkey: "c".repeat(64),
+    lightningAddress: "creator@example.com",
+    tags: [["d", "pointer"]],
+    kind: 30078,
+  };
+
+  globalThis.__BITVID_PLATFORM_FEE_OVERRIDE__ = "70/30";
+  const seventyThirty = createDeps();
+  const ratioResult = await splitAndZap(
+    { videoEvent, amountSats: 1000, comment: "Great video!" },
+    seventyThirty.deps
+  );
+
+  assert.equal(ratioResult.creatorShare, 700);
+  assert.equal(ratioResult.platformShare, 300);
+  const ratioSendCalls = seventyThirty.getSendCalls();
+  assert.equal(ratioSendCalls.length, 2, "should send two payments for ratio");
+  assert.equal(ratioSendCalls[0].amountSats, 700);
+  assert.equal(ratioSendCalls[1].amountSats, 300);
+
+  globalThis.__BITVID_PLATFORM_FEE_OVERRIDE__ = "30%";
+  const percentOverride = createDeps();
+  const percentResult = await splitAndZap(
+    { videoEvent, amountSats: 200, comment: "Another zap" },
+    percentOverride.deps
+  );
+
+  assert.equal(percentResult.creatorShare, 140);
+  assert.equal(percentResult.platformShare, 60);
+
+  delete globalThis.__BITVID_PLATFORM_FEE_OVERRIDE__;
+}
+
 async function testLnurlBounds() {
   globalThis.__BITVID_PLATFORM_FEE_OVERRIDE__ = 0;
   const depsWrapper = createDeps({ minSendable: 5_000 });
@@ -265,5 +301,6 @@ await testSplitMath();
 await testLnurlBounds();
 await testMissingAddress();
 await testWalletFailure();
+await testStringFeeOverride();
 
 console.log("zap-split tests passed");