diff --git a/index.js b/index.js
index 2251c18..bd3904b 100644
--- a/index.js
+++ b/index.js
@@ -1,6 +1,7 @@
 'use strict'
 const From = require('fastify-reply-from')
 const WebSocket = require('ws')
+const { convertUrlToWebSocket } = require('./utils')
 
 const httpMethods = ['DELETE', 'GET', 'HEAD', 'PATCH', 'POST', 'PUT', 'OPTIONS']
 const urlPattern = /^https?:\/\//
@@ -98,11 +99,11 @@ function setupWebSocketProxy (fastify, options, rewritePrefix) {
   })
 
   function createWebSocketUrl (request) {
-    const source = new URL(request.url, 'http://127.0.0.1')
+    const source = new URL(request.url, 'ws://127.0.0.1')
 
     const target = new URL(
       source.pathname.replace(fastify.prefix, rewritePrefix),
-      options.upstream
+      convertUrlToWebSocket(options.upstream)
     )
 
     target.search = source.search
diff --git a/package.json b/package.json
index 31f730b..a441c51 100644
--- a/package.json
+++ b/package.json
@@ -49,7 +49,7 @@
   },
   "dependencies": {
     "fastify-reply-from": "^6.0.0",
-    "ws": "^7.4.1"
+    "ws": "^8.0.0"
   },
   "tsd": {
     "directory": "test"
diff --git a/test/utils.js b/test/utils.js
new file mode 100644
index 0000000..c1cddeb
--- /dev/null
+++ b/test/utils.js
@@ -0,0 +1,20 @@
+'use strict'
+
+const t = require('tap')
+const { convertUrlToWebSocket } = require('../utils')
+
+t.test('convertUrlToWebSocket', function (t) {
+  const testData = [
+    { input: 'http://localhost', expected: 'ws://localhost' },
+    { input: 'https://localhost', expected: 'wss://localhost' },
+    { input: 'ws://localhost', expected: 'ws://localhost' },
+    { input: 'wss://localhost', expected: 'wss://localhost' },
+    { input: 'wronghttp://localhost', expected: 'wronghttp://localhost' },
+    { input: 'NOT_AN_URL', expected: 'NOT_AN_URL' }
+
+  ]
+  t.plan(testData.length)
+  for (const { input, expected } of testData) {
+    t.equal(convertUrlToWebSocket(input), expected)
+  }
+})
diff --git a/test/websocket.js b/test/websocket.js
index 00667b3..0e19a73 100644
--- a/test/websocket.js
+++ b/test/websocket.js
@@ -28,14 +28,14 @@ test('basic websocket proxy', async (t) => {
 
   const server = Fastify()
   server.register(proxy, {
-    upstream: `http://localhost:${origin.address().port}`,
+    upstream: `ws://localhost:${origin.address().port}`,
     websocket: true
   })
 
   await server.listen(0)
   t.teardown(server.close.bind(server))
 
-  const ws = new WebSocket(`http://localhost:${server.server.address().port}`)
+  const ws = new WebSocket(`ws://localhost:${server.server.address().port}`)
 
   await once(ws, 'open')
 
@@ -58,7 +58,7 @@ test('captures errors on start', async (t) => {
   await app.listen(0)
 
   const app2 = Fastify()
-  app2.register(proxy, { upstream: 'http://localhost', websocket: true })
+  app2.register(proxy, { upstream: 'ws://localhost', websocket: true })
 
   const appPort = app.server.address().port
 
diff --git a/test/ws-prefix-rewrite-core.js b/test/ws-prefix-rewrite-core.js
index 26cb178..711ed62 100644
--- a/test/ws-prefix-rewrite-core.js
+++ b/test/ws-prefix-rewrite-core.js
@@ -8,6 +8,7 @@ const fastifyWebSocket = require('fastify-websocket')
 const proxy = require('..')
 const WebSocket = require('ws')
 const got = require('got')
+const { convertUrlToWebSocket } = require('../utils')
 
 const level = 'warn'
 
@@ -35,7 +36,8 @@ async function proxyServer (t, backendURL, backendPath, proxyOptions, wrapperOpt
 async function processRequest (t, frontendURL, path, expected) {
   const url = new URL(path, frontendURL)
   t.comment('ws connecting to ' + url.toString())
-  const ws = new WebSocket(url)
+  const wsUrl = convertUrlToWebSocket(url.href)
+  const ws = new WebSocket(wsUrl)
   let wsResult, gotResult
 
   try {
diff --git a/test/ws-prefix-rewrite.js b/test/ws-prefix-rewrite.js
index 7da53dc..abc84dd 100644
--- a/test/ws-prefix-rewrite.js
+++ b/test/ws-prefix-rewrite.js
@@ -34,7 +34,8 @@ async function proxyServer (t, backendURL, backendPath, proxyOptions, wrapperOpt
 async function processRequest (t, frontendURL, path, expected) {
   const url = new URL(path, frontendURL)
   t.comment('ws connecting to ' + url.toString())
-  const ws = new WebSocket(url)
+  const wsUrl = url.href.replace('http:', 'ws:')
+  const ws = new WebSocket(wsUrl)
   let wsResult, gotResult
 
   try {
diff --git a/utils.js b/utils.js
new file mode 100644
index 0000000..a9c069d
--- /dev/null
+++ b/utils.js
@@ -0,0 +1,9 @@
+'use strict'
+
+function convertUrlToWebSocket (urlString) {
+  return urlString.replace(/^(http)(s)?:\/\//, 'ws$2://')
+}
+
+module.exports = {
+  convertUrlToWebSocket
+}