diff --git a/.github/workflows/keyboard.yml b/.github/workflows/keyboard.yml
index a8e527b9810..42bc2f52854 100644
--- a/.github/workflows/keyboard.yml
+++ b/.github/workflows/keyboard.yml
@@ -38,6 +38,6 @@ jobs:
       - name: Compile Keyboards
         run: kmc --error-reporting build keyboards/3.0/*.xml
       - name: Check ABNF
-        run: bash tools/scripts/keyboard-abnf-tests/check-keyboard-abnf.sh
+        run: 'cd tools/scripts/keyboard-abnf-tests && npm ci && npm t'
       - name: Run Kbd Charts
         run: 'cd docs/charts/keyboards && npm ci && npm run build'
diff --git a/tools/scripts/keyboard-abnf-tests/.gitignore b/tools/scripts/keyboard-abnf-tests/.gitignore
new file mode 100644
index 00000000000..07e6e472cc7
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/.gitignore
@@ -0,0 +1 @@
+/node_modules
diff --git a/tools/scripts/keyboard-abnf-tests/README.md b/tools/scripts/keyboard-abnf-tests/README.md
new file mode 100644
index 00000000000..a7c724143ea
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/README.md
@@ -0,0 +1,23 @@
+# Keyboard-abnf-tests
+
+Tests for and against the ABNF files, written in Node.js
+
+## To use
+
+- `npm ci`
+- `npm t`
+
+## To update
+
+Note there are four files. There's a `.d` directory for each ABNF file in keyboards/abnf/.  The "pass" files are expected to pass the ABNF and the "fail" to fail it.  Lines beginning with # are comments and skipped.
+
+- transform-from-required.d/from-match.pass.txt
+- transform-from-required.d/from-match.fail.txt
+- transform-to-required.d/to-replacement.pass.txt
+- transform-to-required.d/to-replacement.fail.txt
+
+## Copyright
+
+Copyright © 1991-2025 Unicode, Inc.
+All rights reserved.
+[Terms of use](https://www.unicode.org/copyright.html)
diff --git a/tools/scripts/keyboard-abnf-tests/check-keyboard-abnf.sh b/tools/scripts/keyboard-abnf-tests/check-keyboard-abnf.sh
deleted file mode 100755
index da348c9a46d..00000000000
--- a/tools/scripts/keyboard-abnf-tests/check-keyboard-abnf.sh
+++ /dev/null
@@ -1,57 +0,0 @@
-#!/bin/bash
-
-ABNF_DIR=keyboards/abnf
-TEST_DIR=tools/scripts/keyboard-abnf-tests
-abnf_check="npx --package=abnf abnf_check"
-abnf_test="npx --package=abnf abnf_test"
-TEMP=$(mktemp -d)
-echo "-- checking ABNF --"
-
-for abnf in ${ABNF_DIR}/*.abnf; do
-    echo Validating ${abnf}
-    ${abnf_check} ${abnf} || exit 1
-done
-
-echo "-- running test suites --"
-
-for abnf in ${ABNF_DIR}/*.abnf; do
-    echo Testing ${abnf}
-    base=$(basename ${abnf} .abnf)
-    # fix for node-abnf issue
-    fgrep -v SKIP-NODE-ABNF < ${abnf} > ${TEMP}/${base}.abnf
-    abnf=${TEMP}/${base}.abnf
-    SUITEDIR=${TEST_DIR}/${base}.d
-    if [[ -d ${SUITEDIR} ]];
-    then
-        echo "  Test suite ${SUITEDIR}"
-        for testf in ${SUITEDIR}/*.pass.txt; do
-            start=$(basename ${testf} .pass.txt)
-            echo "   Testing PASS ${testf} for ${start}"
-            while IFS="" read -r str || [ -n "$str" ]
-            do
-                if echo "${str}" | grep -v -q '^#'; then
-                    echo "# '${str}'"
-                    (${abnf_test} ${abnf} -t "${str}") 2>&1 >/dev/null || exit 1
-                fi
-            done <${testf}
-        done
-        for testf in ${SUITEDIR}/*.fail.txt; do
-            start=$(basename ${testf} .fail.txt)
-            echo "   Testing FAIL ${testf} for ${start}"
-            while IFS="" read -r str || [ -n "$str" ]
-            do
-                if echo "${str}" | grep -v -q '^#'; then
-                    echo "# '${str}'"
-                    (${abnf_test} ${abnf} -t "${str}") 2>&1 > /dev/null && (echo ERROR should have failed ; exit 1)
-                fi
-            done <${testf}
-        done
-    else
-        echo "  Warning: ${SUITEDIR} did not exist"
-    fi
-    # npx --package=abnf abnf_check ${abnf} || exit 1
-done
-
-echo "All OK"
-exit 0
-
diff --git a/tools/scripts/keyboard-abnf-tests/lib/index.mjs b/tools/scripts/keyboard-abnf-tests/lib/index.mjs
new file mode 100644
index 00000000000..9add5715d65
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/lib/index.mjs
@@ -0,0 +1,123 @@
+// Copyright (c) 2025 Unicode, Inc.
+// For terms of use, see http://www.unicode.org/copyright.html
+// SPDX-License-Identifier: Unicode-3.0
+
+import { XMLParser } from "fast-xml-parser";
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+import * as abnf from "abnf";
+import peggy from "peggy";
+
+/** relative path to ABNF */
+export const ABNF_DIR = "../../../keyboards/abnf";
+
+/**
+ * @param {string} abnfPath path to .abnf file
+ * @returns the raw parser
+ */
+export async function getAbnfParser(abnfPath) {
+  const parsed = await abnf.parseFile(abnfPath);
+  const opts = {
+    grammarSource: abnfPath,
+    trace: false,
+  };
+  const text = parsed.toFormat({ format: "peggy" });
+  const parser = peggy.generate(text, opts);
+
+  return parser;
+}
+
+/**
+ * @param {string} abnfPath path to .abnf file
+ * @param {Object} parser parser from getAbnfParser
+ * @returns function taking a string and returning results (or throwing)
+ */
+export async function getParseFunction(abnfPath) {
+  const parser = await getAbnfParser(abnfPath);
+  const opts = {
+    grammarSource: abnfPath,
+    trace: false,
+  };
+  const fn = (str) => parser.parse(str, opts);
+  return fn;
+}
+
+/**
+ * Check XML file for valid transform from= and to=
+ * @param {string} path path to keyboard XML
+ * @returns true if OK,otherwise throws
+ */
+export async function checkXml(path) {
+  // load the ABNF files. This creates two functions, parseFrom and parseTo
+  // that can take any text and match against the grammar.
+
+  const parseFrom = await getParseFunction(
+    join(ABNF_DIR, "transform-from-required.abnf")
+  );
+  const parseTo = await getParseFunction(
+    join(ABNF_DIR, "transform-to-required.abnf")
+  );
+
+  // read the XML and parse it
+  const text = readFileSync(path);
+  const parser = new XMLParser({
+    ignoreAttributes: false,
+    trimValues: false,
+    htmlEntities: true,
+  });
+  const r = parser.parse(text, false);
+
+  // pull out the transforms
+  let transforms = r?.keyboard3?.transforms;
+
+  if (!transforms) return true; // no transforms
+
+  // If there's only one element, it will be element: {} instead of element: [{ … }]
+  // this is how the XML parser works. We convert it to an array for processing.
+  if (!Array.isArray(transforms)) {
+    transforms = [transforms];
+  }
+
+  for (const transformSet of transforms) {
+    let transformGroups = transformSet?.transformGroup;
+
+    if (!transformGroups) continue; // no transforms
+
+    // If there's only one element, it will be element: {} instead of element: [{ … }]
+    // this is how the XML parser works. We convert it to an array for processing.
+    if (!Array.isArray(transformGroups)) {
+      // there was only one transformGroup
+      transformGroups = [transformGroups];
+    }
+
+    for (const transformGroup of transformGroups) {
+      let transforms = transformGroup?.transform;
+      if (!transforms) continue;
+
+      // If there's only one element, it will be element: {} instead of element: [{ … }]
+      // this is how the XML parser works. We convert it to an array for processing.
+      if (!Array.isArray(transforms)) {
+        transforms = [transforms];
+      }
+      for (const transform of transforms) {
+        // Check the from= string against the from ABNF
+        const fromStr = transform["@_from"];
+        try {
+          parseFrom(fromStr);
+        } catch (e) {
+          throw Error(`Bad from="${fromStr}"`, { cause: e });
+        }
+        // Check the to= string against the to ABNF
+        const toStr = transform["@_to"];
+        if (toStr) { // it's legal to have a missing to=
+          try {
+            parseTo(toStr);
+          } catch (e) {
+            throw Error(`Bad to="${toStr}"`, { cause: e });
+          }
+        }
+      }
+    }
+  }
+  return true;
+}
diff --git a/tools/scripts/keyboard-abnf-tests/lib/util.mjs b/tools/scripts/keyboard-abnf-tests/lib/util.mjs
new file mode 100644
index 00000000000..dffabd4c463
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/lib/util.mjs
@@ -0,0 +1,22 @@
+// Copyright (c) 2025 Unicode, Inc.
+// For terms of use, see http://www.unicode.org/copyright.html
+// SPDX-License-Identifier: Unicode-3.0
+
+import { readFileSync, readdirSync } from "node:fs";
+import { join } from "node:path";
+import { ABNF_DIR } from "./index.mjs";
+
+/**
+ *
+ * @param {function} callback  given abnfFile, abnfPath, abnfText
+ */
+export async function forEachAbnf(callback) {
+  return await Promise.all(
+    readdirSync(ABNF_DIR).map((abnfFile) => {
+      if (!/^.*\.abnf$/.test(abnfFile)) return;
+      const abnfPath = join(ABNF_DIR, abnfFile);
+      const abnfText = readFileSync(abnfPath);
+      return callback({ abnfFile, abnfPath, abnfText });
+    })
+  );
+}
diff --git a/tools/scripts/keyboard-abnf-tests/package-lock.json b/tools/scripts/keyboard-abnf-tests/package-lock.json
new file mode 100644
index 00000000000..37e8089e870
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/package-lock.json
@@ -0,0 +1,124 @@
+{
+  "name": "@unicode-org/keyboard-abnf-tests",
+  "version": "1.0.0",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "@unicode-org/keyboard-abnf-tests",
+      "version": "1.0.0",
+      "license": "Unicode-3.0",
+      "dependencies": {
+        "abnf": "^4.3.1",
+        "fast-xml-parser": "^4.5.1",
+        "peggy": "^4.2.0"
+      }
+    },
+    "node_modules/@peggyjs/from-mem": {
+      "version": "1.3.5",
+      "resolved": "https://registry.npmjs.org/@peggyjs/from-mem/-/from-mem-1.3.5.tgz",
+      "integrity": "sha512-oRyzXE7nirAn+5yYjCdWQHg3EG2XXcYRoYNOK8Quqnmm+9FyK/2YWVunwudlYl++M3xY+gIAdf0vAYS+p0nKfQ==",
+      "dependencies": {
+        "semver": "7.6.3"
+      },
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/abnf": {
+      "version": "4.3.1",
+      "resolved": "https://registry.npmjs.org/abnf/-/abnf-4.3.1.tgz",
+      "integrity": "sha512-j4A8wWqKqkcSjx5xFESo9GtW2EUvlUZutcWB1knhxSP9kaXJ/YwL0g6dvMhHRjCPCNsIWwNGoKMHzPwemSpCvw==",
+      "dependencies": {
+        "commander": "^13.0.0",
+        "peggy": "^4.2.0"
+      },
+      "bin": {
+        "abnf_ast": "bin/abnf_ast.js",
+        "abnf_check": "bin/abnf_check.js",
+        "abnf_gen": "bin/abnf_gen.js",
+        "abnf_test": "bin/abnf_test.js"
+      },
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/commander": {
+      "version": "13.0.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-13.0.0.tgz",
+      "integrity": "sha512-oPYleIY8wmTVzkvQq10AEok6YcTC4sRUBl8F9gVuwchGVUCTbl/vhLTaQqutuuySYOsu8YTgV+OxKc/8Yvx+mQ==",
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/fast-xml-parser": {
+      "version": "4.5.1",
+      "resolved": "https://registry.npmjs.org/fast-xml-parser/-/fast-xml-parser-4.5.1.tgz",
+      "integrity": "sha512-y655CeyUQ+jj7KBbYMc4FG01V8ZQqjN+gDYGJ50RtfsUB8iG9AmwmwoAgeKLJdmueKKMrH1RJ7yXHTSoczdv5w==",
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/NaturalIntelligence"
+        },
+        {
+          "type": "paypal",
+          "url": "https://paypal.me/naturalintelligence"
+        }
+      ],
+      "dependencies": {
+        "strnum": "^1.0.5"
+      },
+      "bin": {
+        "fxparser": "src/cli/cli.js"
+      }
+    },
+    "node_modules/peggy": {
+      "version": "4.2.0",
+      "resolved": "https://registry.npmjs.org/peggy/-/peggy-4.2.0.tgz",
+      "integrity": "sha512-ZjzyJYY8NqW8JOZr2PbS/J0UH/hnfGALxSDsBUVQg5Y/I+ZaPuGeBJ7EclUX2RvWjhlsi4pnuL1C/K/3u+cDeg==",
+      "dependencies": {
+        "@peggyjs/from-mem": "1.3.5",
+        "commander": "^12.1.0",
+        "source-map-generator": "0.8.0"
+      },
+      "bin": {
+        "peggy": "bin/peggy.js"
+      },
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/peggy/node_modules/commander": {
+      "version": "12.1.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-12.1.0.tgz",
+      "integrity": "sha512-Vw8qHK3bZM9y/P10u3Vib8o/DdkvA2OtPtZvD871QKjy74Wj1WSKFILMPRPSdUSx5RFK1arlJzEtA4PkFgnbuA==",
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/semver": {
+      "version": "7.6.3",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-7.6.3.tgz",
+      "integrity": "sha512-oVekP1cKtI+CTDvHWYFUcMtsK/00wmAEfyqKfNdARm8u1wNVhSgaX7A8d4UuIlUI5e84iEwOhs7ZPYRmzU9U6A==",
+      "bin": {
+        "semver": "bin/semver.js"
+      },
+      "engines": {
+        "node": ">=10"
+      }
+    },
+    "node_modules/source-map-generator": {
+      "version": "0.8.0",
+      "resolved": "https://registry.npmjs.org/source-map-generator/-/source-map-generator-0.8.0.tgz",
+      "integrity": "sha512-psgxdGMwl5MZM9S3FWee4EgsEaIjahYV5AzGnwUvPhWeITz/j6rKpysQHlQ4USdxvINlb8lKfWGIXwfkrgtqkA==",
+      "engines": {
+        "node": ">= 10"
+      }
+    },
+    "node_modules/strnum": {
+      "version": "1.0.5",
+      "resolved": "https://registry.npmjs.org/strnum/-/strnum-1.0.5.tgz",
+      "integrity": "sha512-J8bbNyKKXl5qYcR36TIO8W3mVGVHrmmxsd5PAItGkmyzwJvybiw2IVq5nqd0i4LSNSkB/sx9VHllbfFdr9k1JA=="
+    }
+  }
+}
diff --git a/tools/scripts/keyboard-abnf-tests/package.json b/tools/scripts/keyboard-abnf-tests/package.json
new file mode 100644
index 00000000000..1bcfdb96f4a
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/package.json
@@ -0,0 +1,18 @@
+{
+  "name": "@unicode-org/keyboard-abnf-tests",
+  "version": "1.0.0",
+  "main": "index.js",
+  "scripts": {
+    "test": "node --test"
+  },
+  "keywords": [],
+  "author": "Steven R. Loomis <srl295@codehivetx.us>",
+  "license": "Unicode-3.0",
+  "description": "Tests for the keyboard ABNF",
+  "private": true,
+  "dependencies": {
+    "abnf": "^4.3.1",
+    "fast-xml-parser": "^4.5.1",
+    "peggy": "^4.2.0"
+  }
+}
diff --git a/tools/scripts/keyboard-abnf-tests/test/abnf-valid.test.mjs b/tools/scripts/keyboard-abnf-tests/test/abnf-valid.test.mjs
new file mode 100644
index 00000000000..91b8e005446
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/test/abnf-valid.test.mjs
@@ -0,0 +1,24 @@
+// Copyright (c) 2025 Unicode, Inc.
+// For terms of use, see http://www.unicode.org/copyright.html
+// SPDX-License-Identifier: Unicode-3.0
+
+import * as abnf from "abnf";
+import { test } from "node:test";
+import * as assert from "node:assert";
+import { forEachAbnf } from "../lib/util.mjs";
+
+function check_refs(parsed) {
+  const errs = abnf.checkRefs(parsed);
+  if (!errs) return 0;
+  for (const err of errs) {
+    console.error(err);
+  }
+  return 3;
+}
+
+await forEachAbnf(async ({ abnfFile, abnfText, abnfPath }) => {
+  await test(`Test validity: ${abnfFile}`, async (t) => {
+    const parsed = await abnf.parseFile(abnfPath);
+    assert.equal(check_refs(parsed), 0);
+  });
+});
diff --git a/tools/scripts/keyboard-abnf-tests/test/datadriven.test.mjs b/tools/scripts/keyboard-abnf-tests/test/datadriven.test.mjs
new file mode 100644
index 00000000000..b655e80caff
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/test/datadriven.test.mjs
@@ -0,0 +1,63 @@
+// Copyright (c) 2025 Unicode, Inc.
+// For terms of use, see http://www.unicode.org/copyright.html
+// SPDX-License-Identifier: Unicode-3.0
+
+import { existsSync, readFileSync, readdirSync } from "node:fs";
+import { test } from "node:test";
+import { basename, join } from "node:path";
+import * as assert from "node:assert";
+import { forEachAbnf } from "../lib/util.mjs";
+import { getParseFunction } from "../lib/index.mjs";
+
+async function assertTest({ t, abnfPath, testText, expect }) {
+  const parser = await getParseFunction(abnfPath);
+  for (const str of testText
+    .trim()
+    .split("\n")
+    .filter((l) => !/^#/.test(l))) {
+    await t.test(`"${str}"`, async (t) => {
+      if (!expect) {
+        assert.throws(
+          () => parser(str),
+          `Expected this expression to fail parsing`
+        );
+      } else {
+        const results = parser(str);
+        assert.ok(results);
+      }
+    });
+  }
+}
+
+await forEachAbnf(async ({ abnfFile, abnfText, abnfPath }) => {
+  await test(`Test Data: ${abnfFile}`, async (t) => {
+    const stub = basename(abnfFile, ".abnf");
+    const testDir = `./${stub}.d`;
+    assert.ok(existsSync(testDir), `No test dir: ${testDir}`);
+    const tests = readdirSync(testDir)?.filter((f) =>
+      /^.*\.(pass|fail)\.txt/.test(f)
+    );
+    assert.ok(tests && tests.length, `No tests in ${testDir}`);
+    for (const testFile of tests) {
+      if (testFile.endsWith(".pass.txt")) {
+        await t.test(`${stub}/${testFile}`, async (t) => {
+          await assertTest({
+            t,
+            abnfPath,
+            testText: readFileSync(join(testDir, testFile), "utf-8"),
+            expect: true,
+          });
+        });
+      } else if (testFile.endsWith(".fail.txt")) {
+        await t.test(`${stub}/${testFile}`, async (t) => {
+          await assertTest({
+            t,
+            abnfPath,
+            testText: readFileSync(join(testDir, testFile), "utf-8"),
+            expect: false,
+          });
+        });
+      } else throw Error(`Unknown testFile ${testFile}`);
+    }
+  });
+});
diff --git a/tools/scripts/keyboard-abnf-tests/test/xml.test.mjs b/tools/scripts/keyboard-abnf-tests/test/xml.test.mjs
new file mode 100644
index 00000000000..49d423f02a1
--- /dev/null
+++ b/tools/scripts/keyboard-abnf-tests/test/xml.test.mjs
@@ -0,0 +1,22 @@
+// Copyright (c) 2025 Unicode, Inc.
+// For terms of use, see http://www.unicode.org/copyright.html
+// SPDX-License-Identifier: Unicode-3.0
+
+import { join } from "node:path";
+import { readdirSync } from "node:fs";
+import { test } from "node:test";
+import { checkXml } from "../lib/index.mjs";
+
+const KBD_DIR = "../../../keyboards/3.0";
+
+await test("Testing Keyboard XML files for valid transform from/to attributes", async (t) => {
+  // keyboards, excluding -test.xml files
+  const kbds = readdirSync(KBD_DIR).filter((f) =>
+    /^.*(?<!-test)\.xml$/.test(f)
+  );
+  for (const kbd of kbds) {
+    await t.test(`Testing ${kbd}`, async (t) => {
+      await checkXml(join(KBD_DIR, kbd));
+    });
+  }
+});