diff --git a/.npmignore b/.npmignore
index 80e59ef52..53fc9efa9 100644
--- a/.npmignore
+++ b/.npmignore
@@ -1,2 +1,3 @@
+coverage
 tests
 node_modules
diff --git a/package.json b/package.json
index 05f026c0a..69d68d1bb 100644
--- a/package.json
+++ b/package.json
@@ -42,18 +42,20 @@
   },
   "scripts": {
     "test": "npm run lint && node node_modules/.bin/taper tests/test-*.js && npm run test-browser && npm run clean",
-    "test-browser": "browserify tests/browser/test.js -o tests/browser/test-browser.js && node tests/browser/start.js",
-    "lint": "node node_modules/.bin/eslint lib/ *.js tests/ && echo Lint passed.",
-    "clean": "rm tests/browser/test-browser.js || true"
+    "test-browser": "node tests/browser/start.js",
+    "lint": "node node_modules/.bin/eslint lib/ *.js tests/ && echo Lint passed."
   },
   "devDependencies": {
     "browserify": "~5.9.1",
+    "browserify-istanbul": "~0.1.3",
     "coveralls": "~2.11.2",
     "eslint": "0.5.1",
     "function-bind": "~1.0.0",
     "istanbul": "~0.3.2",
     "karma": "~0.12.21",
+    "karma-browserify": "~3.0.1",
     "karma-cli": "0.0.4",
+    "karma-coverage": "0.2.6",
     "karma-phantomjs-launcher": "~0.1.4",
     "karma-tap": "~1.0.1",
     "rimraf": "~2.2.8",
diff --git a/tests/browser/karma.conf.js b/tests/browser/karma.conf.js
index f5c308f8e..6c9311bb0 100644
--- a/tests/browser/karma.conf.js
+++ b/tests/browser/karma.conf.js
@@ -1,15 +1,20 @@
 'use strict'
+var istanbul = require('browserify-istanbul')
 
 module.exports = function(config) {
   config.set({
-    basePath: '',
-    frameworks: ['tap'],
+    basePath: '../..',
+    frameworks: ['tap', 'browserify'],
+    preprocessors: {
+      'tests/browser/test.js': ['browserify'],
+      '*.js,!(tests)/**/*.js': ['coverage']
+    },
     files: [
-      'test-browser.js'
+      'tests/browser/test.js'
     ],
     port: 9876,
 
-    reporters: ['dots'],
+    reporters: ['dots', 'coverage'],
 
     colors: true,
 
@@ -21,6 +26,23 @@ module.exports = function(config) {
 
     singleRun: true,
 
+    plugins: [
+      'karma-phantomjs-launcher',
+      'karma-coverage',
+      'karma-browserify',
+      'karma-tap'
+    ],
+    browserify: {
+      debug: true,
+      transform: [istanbul({
+        ignore: ['**/node_modules/**', '**/tests/**']
+      })]
+    },
+    coverageReporter: {
+      type: 'lcov',
+      dir: 'coverage/'
+    },
+
     // Custom launcher to allowe self signed certs.
     customLaunchers: {
       PhantomJS_without_security: {
diff --git a/tests/browser/start.js b/tests/browser/start.js
index 0027f2612..c515f2be3 100644
--- a/tests/browser/start.js
+++ b/tests/browser/start.js
@@ -26,6 +26,7 @@ server.listen(port, function() {
     path.join(__dirname, '/karma.conf.js')
   ])
   c.stdout.pipe(process.stdout)
+  c.stderr.pipe(process.stderr)
   c.on('exit', function(c) {
     // Exit process with karma exit code.
     if (c !== 0) {