diff --git a/test/parallel/test-whatwg-encoding-api-basics.js b/test/parallel/test-whatwg-encoding-api-basics.js
deleted file mode 100644
index 8abaee817156f4..00000000000000
--- a/test/parallel/test-whatwg-encoding-api-basics.js
+++ /dev/null
@@ -1,74 +0,0 @@
-'use strict';
-
-// From: https://github.com/w3c/web-platform-tests/blob/master/encoding/api-basics.html
-// TODO(joyeecheung): replace this with WPT
-
-const common = require('../common');
-
-if (!common.hasIntl)
-  common.skip('missing Intl');
-
-const assert = require('assert');
-
-function testDecodeSample(encoding, string, bytes) {
-  assert.strictEqual(
-    new TextDecoder(encoding).decode(new Uint8Array(bytes)),
-    string);
-  assert.strictEqual(
-    new TextDecoder(encoding).decode(new Uint8Array(bytes).buffer),
-    string);
-}
-
-// `z` (ASCII U+007A), cent (Latin-1 U+00A2), CJK water (BMP U+6C34),
-// G-Clef (non-BMP U+1D11E), PUA (BMP U+F8FF), PUA (non-BMP U+10FFFD)
-// byte-swapped BOM (non-character U+FFFE)
-const sample = 'z\xA2\u6C34\uD834\uDD1E\uF8FF\uDBFF\uDFFD\uFFFE';
-
-{
-  const encoding = 'utf-8';
-  const string = sample;
-  const bytes = [
-    0x7A, 0xC2, 0xA2, 0xE6, 0xB0, 0xB4,
-    0xF0, 0x9D, 0x84, 0x9E, 0xEF, 0xA3,
-    0xBF, 0xF4, 0x8F, 0xBF, 0xBD, 0xEF,
-    0xBF, 0xBE
-  ];
-  const encoded = new TextEncoder().encode(string);
-  assert.deepStrictEqual([].slice.call(encoded), bytes);
-  assert.strictEqual(
-    new TextDecoder(encoding).decode(new Uint8Array(bytes)),
-    string);
-  assert.strictEqual(
-    new TextDecoder(encoding).decode(new Uint8Array(bytes).buffer),
-    string);
-}
-
-testDecodeSample(
-  'utf-16le',
-  sample,
-  [
-    0x7A, 0x00, 0xA2, 0x00, 0x34, 0x6C,
-    0x34, 0xD8, 0x1E, 0xDD, 0xFF, 0xF8,
-    0xFF, 0xDB, 0xFD, 0xDF, 0xFE, 0xFF
-  ]
-);
-
-testDecodeSample(
-  'utf-16be',
-  sample,
-  [
-    0x00, 0x7A, 0x00, 0xA2, 0x6C, 0x34,
-    0xD8, 0x34, 0xDD, 0x1E, 0xF8, 0xFF,
-    0xDB, 0xFF, 0xDF, 0xFD, 0xFF, 0xFE
-  ]
-);
-
-testDecodeSample(
-  'utf-16',
-  sample,
-  [
-    0x7A, 0x00, 0xA2, 0x00, 0x34, 0x6C,
-    0x34, 0xD8, 0x1E, 0xDD, 0xFF, 0xF8,
-    0xFF, 0xDB, 0xFD, 0xDF, 0xFE, 0xFF
-  ]
-);
diff --git a/test/parallel/test-whatwg-encoding-custom-fatal-streaming.js b/test/parallel/test-whatwg-encoding-custom-fatal-streaming.js
index d1199874871133..50e054c08cade8 100644
--- a/test/parallel/test-whatwg-encoding-custom-fatal-streaming.js
+++ b/test/parallel/test-whatwg-encoding-custom-fatal-streaming.js
@@ -8,8 +8,6 @@ const common = require('../common');
 if (!common.hasIntl)
   common.skip('missing Intl');
 
-const assert = require('assert');
-
 {
   [
     { encoding: 'utf-8', sequence: [0xC0] },
@@ -28,12 +26,6 @@ const assert = require('assert');
           `The encoded data was not valid for encoding ${testCase.encoding}`
       }
     );
-
-    // TODO(joyeecheung): remove this when WPT is ported
-    assert.strictEqual(
-      new TextDecoder(testCase.encoding).decode(data),
-      '\uFFFD'
-    );
   });
 }
 
@@ -42,10 +34,6 @@ const assert = require('assert');
   const odd = new Uint8Array([0x00]);
   const even = new Uint8Array([0x00, 0x00]);
 
-  // TODO(joyeecheung): remove this when WPT is ported
-  assert.strictEqual(decoder.decode(odd, { stream: true }), '');
-  assert.strictEqual(decoder.decode(odd), '\u0000');
-
   common.expectsError(
     () => {
       decoder.decode(even, { stream: true });
@@ -69,8 +57,4 @@ const assert = require('assert');
         'The encoded data was not valid for encoding utf-16le'
     }
   );
-
-  // TODO(joyeecheung): remove this when WPT is ported
-  assert.strictEqual(decoder.decode(even, { stream: true }), '\u0000');
-  assert.strictEqual(decoder.decode(even), '\u0000');
 }
diff --git a/test/parallel/test-whatwg-encoding-custom-textdecoder-fatal.js b/test/parallel/test-whatwg-encoding-custom-textdecoder-fatal.js
index c5e4b9684b190f..08406386a1a253 100644
--- a/test/parallel/test-whatwg-encoding-custom-textdecoder-fatal.js
+++ b/test/parallel/test-whatwg-encoding-custom-textdecoder-fatal.js
@@ -8,8 +8,6 @@ const common = require('../common');
 if (!common.hasIntl)
   common.skip('missing Intl');
 
-const assert = require('assert');
-
 const bad = [
   { encoding: 'utf-8', input: [0xFF], name: 'invalid code' },
   { encoding: 'utf-8', input: [0xC0], name: 'ends early' },
@@ -82,11 +80,3 @@ bad.forEach((t) => {
     }
   );
 });
-
-// TODO(joyeecheung): remove this when WPT is ported
-{
-  assert('fatal' in new TextDecoder());
-  assert.strictEqual(typeof new TextDecoder().fatal, 'boolean');
-  assert(!new TextDecoder().fatal);
-  assert(new TextDecoder('utf-8', { fatal: true }).fatal);
-}
diff --git a/test/parallel/test-whatwg-encoding-custom-textdecoder-utf16-surrogates.js b/test/parallel/test-whatwg-encoding-custom-textdecoder-utf16-surrogates.js
index 3af83e01b0450d..bba10fbd2279a2 100644
--- a/test/parallel/test-whatwg-encoding-custom-textdecoder-utf16-surrogates.js
+++ b/test/parallel/test-whatwg-encoding-custom-textdecoder-utf16-surrogates.js
@@ -8,8 +8,6 @@ const common = require('../common');
 if (!common.hasIntl)
   common.skip('missing Intl');
 
-const assert = require('assert');
-
 const bad = [
   {
     encoding: 'utf-16le',
@@ -44,11 +42,6 @@ const bad = [
 ];
 
 bad.forEach((t) => {
-  // TODO(joyeecheung): remove this when WPT is ported
-  assert.strictEqual(
-    new TextDecoder(t.encoding).decode(new Uint8Array(t.input)),
-    t.expected);
-
   common.expectsError(
     () => {
       new TextDecoder(t.encoding, { fatal: true })
diff --git a/test/parallel/test-whatwg-encoding-surrogates-utf8.js b/test/parallel/test-whatwg-encoding-surrogates-utf8.js
deleted file mode 100644
index 7a155cdc537a9c..00000000000000
--- a/test/parallel/test-whatwg-encoding-surrogates-utf8.js
+++ /dev/null
@@ -1,53 +0,0 @@
-'use strict';
-
-// From: https://github.com/w3c/web-platform-tests/blob/fa9436d12c/encoding/api-surrogates-utf8.html
-// TODO(joyeecheung): replace this with WPT
-
-require('../common');
-
-const assert = require('assert');
-
-const badStrings = [
-  {
-    input: 'abc123',
-    expected: [0x61, 0x62, 0x63, 0x31, 0x32, 0x33],
-    decoded: 'abc123',
-    name: 'Sanity check'
-  },
-  {
-    input: '\uD800',
-    expected: [0xef, 0xbf, 0xbd],
-    decoded: '\uFFFD',
-    name: 'Surrogate half (low)'
-  },
-  {
-    input: '\uDC00',
-    expected: [0xef, 0xbf, 0xbd],
-    decoded: '\uFFFD',
-    name: 'Surrogate half (high)'
-  },
-  {
-    input: 'abc\uD800123',
-    expected: [0x61, 0x62, 0x63, 0xef, 0xbf, 0xbd, 0x31, 0x32, 0x33],
-    decoded: 'abc\uFFFD123',
-    name: 'Surrogate half (low), in a string'
-  },
-  {
-    input: 'abc\uDC00123',
-    expected: [0x61, 0x62, 0x63, 0xef, 0xbf, 0xbd, 0x31, 0x32, 0x33],
-    decoded: 'abc\uFFFD123',
-    name: 'Surrogate half (high), in a string'
-  },
-  {
-    input: '\uDC00\uD800',
-    expected: [0xef, 0xbf, 0xbd, 0xef, 0xbf, 0xbd],
-    decoded: '\uFFFD\uFFFD',
-    name: 'Wrong order'
-  }
-];
-
-badStrings.forEach((t) => {
-  const encoded = new TextEncoder().encode(t.input);
-  assert.deepStrictEqual([].slice.call(encoded), t.expected);
-  assert.strictEqual(new TextDecoder('utf-8').decode(encoded), t.decoded);
-});
diff --git a/test/parallel/test-whatwg-encoding-textdecoder-ignorebom.js b/test/parallel/test-whatwg-encoding-textdecoder-ignorebom.js
deleted file mode 100644
index 7421965c9fb517..00000000000000
--- a/test/parallel/test-whatwg-encoding-textdecoder-ignorebom.js
+++ /dev/null
@@ -1,44 +0,0 @@
-'use strict';
-
-// From: https://github.com/w3c/web-platform-tests/blob/7f567fa29c/encoding/textdecoder-ignorebom.html
-// TODO(joyeecheung): replace this with WPT
-
-const common = require('../common');
-
-if (!common.hasIntl)
-  common.skip('missing Intl');
-
-const assert = require('assert');
-
-const cases = [
-  {
-    encoding: 'utf-8',
-    bytes: [0xEF, 0xBB, 0xBF, 0x61, 0x62, 0x63]
-  },
-  {
-    encoding: 'utf-16le',
-    bytes: [0xFF, 0xFE, 0x61, 0x00, 0x62, 0x00, 0x63, 0x00]
-  },
-  {
-    encoding: 'utf-16be',
-    bytes: [0xFE, 0xFF, 0x00, 0x61, 0x00, 0x62, 0x00, 0x63]
-  }
-];
-
-cases.forEach((testCase) => {
-  const BOM = '\uFEFF';
-  let decoder = new TextDecoder(testCase.encoding, { ignoreBOM: true });
-  const bytes = new Uint8Array(testCase.bytes);
-  assert.strictEqual(decoder.decode(bytes), `${BOM}abc`);
-  decoder = new TextDecoder(testCase.encoding, { ignoreBOM: false });
-  assert.strictEqual(decoder.decode(bytes), 'abc');
-  decoder = new TextDecoder(testCase.encoding);
-  assert.strictEqual(decoder.decode(bytes), 'abc');
-});
-
-{
-  assert('ignoreBOM' in new TextDecoder());
-  assert.strictEqual(typeof new TextDecoder().ignoreBOM, 'boolean');
-  assert(!new TextDecoder().ignoreBOM);
-  assert(new TextDecoder('utf-8', { ignoreBOM: true }).ignoreBOM);
-}
diff --git a/test/parallel/test-whatwg-encoding-textdecoder-streaming.js b/test/parallel/test-whatwg-encoding-textdecoder-streaming.js
deleted file mode 100644
index acc39a74e5cf56..00000000000000
--- a/test/parallel/test-whatwg-encoding-textdecoder-streaming.js
+++ /dev/null
@@ -1,50 +0,0 @@
-'use strict';
-
-// From: https://github.com/w3c/web-platform-tests/blob/fa9436d12c/encoding/textdecoder-streaming.html
-// TODO(joyeecheung): replace this with WPT
-
-const common = require('../common');
-
-if (!common.hasIntl)
-  common.skip('missing Intl');
-
-const assert = require('assert');
-
-const string =
-  '\x00123ABCabc\x80\xFF\u0100\u1000\uFFFD\uD800\uDC00\uDBFF\uDFFF';
-const octets = {
-  'utf-8': [
-    0x00, 0x31, 0x32, 0x33, 0x41, 0x42, 0x43, 0x61, 0x62, 0x63, 0xc2, 0x80,
-    0xc3, 0xbf, 0xc4, 0x80, 0xe1, 0x80, 0x80, 0xef, 0xbf, 0xbd, 0xf0, 0x90,
-    0x80, 0x80, 0xf4, 0x8f, 0xbf, 0xbf],
-  'utf-16le': [
-    0x00, 0x00, 0x31, 0x00, 0x32, 0x00, 0x33, 0x00, 0x41, 0x00, 0x42, 0x00,
-    0x43, 0x00, 0x61, 0x00, 0x62, 0x00, 0x63, 0x00, 0x80, 0x00, 0xFF, 0x00,
-    0x00, 0x01, 0x00, 0x10, 0xFD, 0xFF, 0x00, 0xD8, 0x00, 0xDC, 0xFF, 0xDB,
-    0xFF, 0xDF],
-  'utf-16be': [
-    0x00, 0x00, 0x00, 0x31, 0x00, 0x32, 0x00, 0x33, 0x00, 0x41, 0x00, 0x42,
-    0x00, 0x43, 0x00, 0x61, 0x00, 0x62, 0x00, 0x63, 0x00, 0x80, 0x00, 0xFF,
-    0x01, 0x00, 0x10, 0x00, 0xFF, 0xFD, 0xD8, 0x00, 0xDC, 0x00, 0xDB, 0xFF,
-    0xDF, 0xFF]
-};
-
-Object.keys(octets).forEach((encoding) => {
-  if (encoding === 'utf-16be' && !common.hasIntl) {
-    console.log('skipping utf-16be because missing Intl');
-    return;
-  }
-  for (let len = 1; len <= 5; ++len) {
-    const encoded = octets[encoding];
-    const decoder = new TextDecoder(encoding);
-    let out = '';
-    for (let i = 0; i < encoded.length; i += len) {
-      const sub = [];
-      for (let j = i; j < encoded.length && j < i + len; ++j)
-        sub.push(encoded[j]);
-      out += decoder.decode(new Uint8Array(sub), { stream: true });
-    }
-    out += decoder.decode();
-    assert.strictEqual(out, string);
-  }
-});
diff --git a/test/parallel/test-whatwg-encoding-textencoder-utf16-surrogates.js b/test/parallel/test-whatwg-encoding-textencoder-utf16-surrogates.js
deleted file mode 100644
index 453b49e5b92730..00000000000000
--- a/test/parallel/test-whatwg-encoding-textencoder-utf16-surrogates.js
+++ /dev/null
@@ -1,49 +0,0 @@
-'use strict';
-
-// From: https://github.com/w3c/web-platform-tests/blob/fa9436d12c/encoding/textencoder-utf16-surrogates.html
-// TODO(joyeecheung): replace this with WPT
-
-require('../common');
-
-const assert = require('assert');
-
-const bad = [
-  {
-    input: '\uD800',
-    expected: '\uFFFD',
-    name: 'lone surrogate lead'
-  },
-  {
-    input: '\uDC00',
-    expected: '\uFFFD',
-    name: 'lone surrogate trail'
-  },
-  {
-    input: '\uD800\u0000',
-    expected: '\uFFFD\u0000',
-    name: 'unmatched surrogate lead'
-  },
-  {
-    input: '\uDC00\u0000',
-    expected: '\uFFFD\u0000',
-    name: 'unmatched surrogate trail'
-  },
-  {
-    input: '\uDC00\uD800',
-    expected: '\uFFFD\uFFFD',
-    name: 'swapped surrogate pair'
-  },
-  {
-    input: '\uD834\uDD1E',
-    expected: '\uD834\uDD1E',
-    name: 'properly encoded MUSICAL SYMBOL G CLEF (U+1D11E)'
-  }
-];
-
-bad.forEach((t) => {
-  const encoded = new TextEncoder().encode(t.input);
-  const decoded = new TextDecoder().decode(encoded);
-  assert.strictEqual(decoded, t.expected);
-});
-
-assert.strictEqual(new TextEncoder().encode().length, 0);