diff --git a/.github/workflows/test-all.yml b/.github/workflows/test-all.yml
index 97849d8e41c..f026581403c 100644
--- a/.github/workflows/test-all.yml
+++ b/.github/workflows/test-all.yml
@@ -40,6 +40,8 @@ jobs:
         github-token: ${{ secrets.GITHUB_TOKEN }}
         path-to-lcov: ./lcov-all.info
       continue-on-error: true
+    - name: Generate Size Report
+      run: yarn size-report
   deploy:
     name: Canary Deploy
     runs-on: ubuntu-latest
diff --git a/.github/workflows/test-changed.yml b/.github/workflows/test-changed.yml
index ffe2e9aa4eb..afca6c3b1ee 100644
--- a/.github/workflows/test-changed.yml
+++ b/.github/workflows/test-changed.yml
@@ -28,3 +28,5 @@ jobs:
       run: yarn build
     - name: Run tests on changed packages
       run: xvfb-run yarn test:changed
+    - name: Generate Size Report
+      run: yarn size-report
diff --git a/package.json b/package.json
index ef85fc379c4..eea6e573bf1 100644
--- a/package.json
+++ b/package.json
@@ -37,7 +37,8 @@
     "docgen:node": "node scripts/docgen/generate-docs.js --api node",
     "docgen": "yarn docgen:js; yarn docgen:node",
     "prettier": "prettier --config .prettierrc --write '**/*.{ts,js}'",
-    "lint": "lerna run --scope @firebase/* --scope rxfire lint"
+    "lint": "lerna run --scope @firebase/* --scope rxfire lint",
+    "size-report": "node scripts/report_binary_size.js"
   },
   "repository": {
     "type": "git",
diff --git a/scripts/report_binary_size.js b/scripts/report_binary_size.js
new file mode 100644
index 00000000000..32a5c1212e3
--- /dev/null
+++ b/scripts/report_binary_size.js
@@ -0,0 +1,95 @@
+const { resolve } = require('path');
+const fs = require('fs');
+const { execSync } = require('child_process');
+
+const repoRoot = resolve(__dirname, '..');
+
+const commitHash = process.env.GITHUB_SHA || execSync('git rev-parse HEAD').toString();
+const runId = process.env.GITHUB_RUN_ID || 'local-run-id';
+
+// CDN scripts
+function generateReportForCDNScripts() {
+    const reports = [];
+    const firebaseRoot = resolve(__dirname, '../packages/firebase');
+    const pkgJson = require(`${firebaseRoot}/package.json`);
+    
+    const special_files = [
+        'firebase-performance-standalone.es2017.js',
+        'firebase-performance-standalone.js',
+        'firebase.js'
+    ];
+    
+    const files = [
+        ...special_files.map(file => `${firebaseRoot}/${file}`), 
+        ...pkgJson.components.map(component => `${firebaseRoot}/firebase-${component}.js`)
+    ];
+    
+    for (const file of files) {
+        const { size } = fs.statSync(file);
+        const fileName = file.split('/').slice(-1)[0];
+        reports.push(makeReportObject('firebase', fileName, size));
+    }
+
+    return reports;
+}
+
+// NPM packages
+function generateReportForNPMPackages() {
+    const reports = [];
+    const fields = [
+        'main',
+        'module',
+        'esm2017',
+        'browser',
+        'react-native',
+        'lite',
+        'lite-esm2017'
+    ];
+
+    const packageInfo = JSON.parse(
+        execSync('npx lerna ls --json --scope @firebase/*', { cwd: repoRoot }).toString()
+    );
+
+    for (const package of packageInfo) {
+        const packageJson = require(`${package.location}/package.json`);
+
+        for (const field of fields) {
+            if (packageJson[field]) {
+                const filePath = `${package.location}/${packageJson[field]}`;
+                const { size } = fs.statSync(filePath);
+                reports.push(makeReportObject(packageJson.name, field, size));
+            }
+        }
+    }
+
+    return reports;
+}
+
+function makeReportObject(sdk, type, value) {
+    return {
+        sdk,
+        type,
+        value
+    };
+}
+
+function generateSizeReport() {
+    const reports = [
+        ...generateReportForCDNScripts(),
+        ...generateReportForNPMPackages()
+    ];
+
+    for (const r of reports) {
+        console.log(r.sdk, r.type, r.value);
+    }
+
+    console.log(`Github Action URL: https://github.com/firebase/firebase-js-sdk/actions/runs/${runId}`);
+
+    return {
+        log: `https://github.com/firebase/firebase-js-sdk/actions/runs/${runId}`,
+        metric: "BinarySize",
+        results: reports
+    };
+}
+
+generateSizeReport();