diff --git a/Sources/SwiftNetwork/QUIC/QUICFrame.swift b/Sources/SwiftNetwork/QUIC/QUICFrame.swift
index a9557cf5..54447bbd 100644
--- a/Sources/SwiftNetwork/QUIC/QUICFrame.swift
+++ b/Sources/SwiftNetwork/QUIC/QUICFrame.swift
@@ -773,8 +773,24 @@ struct FramePadding: ~Copyable, QUICFrameProtocol {
     private static func countLeadingZeroBytes(_ bytes: RawSpan) -> Int {
         let count = bytes.byteCount
         let wordSize = MemoryLayout<UInt64>.size
+        let vectorSize = 32
         var offset = 0
 
+        // 1. Speed through the zeros via vectorization.
+        while offset &+ vectorSize <= count {
+            var orResult: UInt8 = 0
+            // This loop is auto-vectorized.
+            for idx in 0..<vectorSize {
+                orResult |= bytes.unsafeLoad(fromUncheckedByteOffset: offset &+ idx, as: UInt8.self)
+            }
+            if orResult == 0 {
+                offset &+= vectorSize
+            } else {
+                break
+            }
+        }
+
+        // 2. Read the rest of the bytes in chunks of words.
         while offset &+ wordSize <= count {
             let word = bytes.unsafeLoadUnaligned(fromByteOffset: offset, as: UInt64.self)
 
@@ -785,6 +801,7 @@ struct FramePadding: ~Copyable, QUICFrameProtocol {
             }
         }
 
+        // 3. Scan the remaining bytes one by one.
         while offset < count, bytes[offset] == 0x00 {
             offset &+= 1
         }
diff --git a/Tests/QUICTests/QUICFrameTests.swift b/Tests/QUICTests/QUICFrameTests.swift
index 2af519a8..0e7bd028 100644
--- a/Tests/QUICTests/QUICFrameTests.swift
+++ b/Tests/QUICTests/QUICFrameTests.swift
@@ -106,8 +106,8 @@ class QUICFrameTests: XCTestCase {
 
     func testPaddingInitStopsAtFirstNonZeroByte() throws {
         // Offset 0 is the frame type byte, so start at 1
-        for sentinelOffset in 1..<23 {
-            var bytes = [UInt8](repeating: 0x00, count: 23)
+        for sentinelOffset in 1..<87 {
+            var bytes = [UInt8](repeating: 0x00, count: 87)
             bytes[sentinelOffset] = 0xff
 
             var frame = Frame(copyBuffer: bytes)
@@ -118,10 +118,10 @@ class QUICFrameTests: XCTestCase {
     }
 
     func testPaddingInitAllZeroes() throws {
-        let bytes = [UInt8](repeating: 0x00, count: 23)
+        let bytes = [UInt8](repeating: 0x00, count: 87)
         var frame = Frame(copyBuffer: bytes)
         let paddingFrame = try FramePadding(frame: &frame, packetNumberSpace: .applicationData)
-        XCTAssertEqual(paddingFrame.extraPadding, 22)
+        XCTAssertEqual(paddingFrame.extraPadding, 86)
         frame.finalize(success: true)
     }