diff --git a/fasthttpproxy/proxy_env.go b/fasthttpproxy/proxy_env.go
index c5abe4a..9d5fe98 100644
--- a/fasthttpproxy/proxy_env.go
+++ b/fasthttpproxy/proxy_env.go
@@ -6,7 +6,7 @@ import (
 	"fmt"
 	"net"
 	"net/url"
-	"sync"
+	"sync/atomic"
 	"time"
 
 	"golang.org/x/net/http/httpproxy"
@@ -32,16 +32,31 @@ func FasthttpProxyHTTPDialer() fasthttp.DialFunc {
 //	c := &fasthttp.Client{
 //		Dial: FasthttpProxyHTTPDialerTimeout(time.Second * 2),
 //	}
+
+const (
+	httpsScheme = "https"
+	tlsPort     = "443"
+)
+
 func FasthttpProxyHTTPDialerTimeout(timeout time.Duration) fasthttp.DialFunc {
 	proxier := httpproxy.FromEnvironment().ProxyFunc()
 
-	// map on proxy URL and its encoded auth barrier
-	authBarriers := map[*url.URL]string{}
-	authBarriersLock := sync.RWMutex{}
+	// encoded auth barrier for http and https proxy.
+	authHTTPStorage := &atomic.Value{}
+	authHTTPSStorage := &atomic.Value{}
 
 	return func(addr string) (net.Conn, error) {
 
-		proxyURL, err := proxier(&url.URL{Host: addr})
+		port, _, err := net.SplitHostPort(addr)
+		if err != nil {
+			return nil, fmt.Errorf("unexpected addr format: %w", err)
+		}
+
+		reqURL := &url.URL{Host: addr, Scheme: httpsScheme}
+		if port == tlsPort {
+			reqURL.Scheme = httpsScheme
+		}
+		proxyURL, err := proxier(reqURL)
 		if err != nil {
 			return nil, err
 		}
@@ -55,28 +70,30 @@ func FasthttpProxyHTTPDialerTimeout(timeout time.Duration) fasthttp.DialFunc {
 
 		var conn net.Conn
 		if timeout == 0 {
-			conn, err = fasthttp.Dial(proxyURL.String())
+			conn, err = fasthttp.Dial(proxyURL.Host)
 		} else {
-			conn, err = fasthttp.DialTimeout(proxyURL.String(), timeout)
+			conn, err = fasthttp.DialTimeout(proxyURL.Host, timeout)
 		}
 		if err != nil {
 			return nil, err
 		}
 
 		req := "CONNECT " + addr + " HTTP/1.1\r\n"
-		if proxyURL.User != nil {
-			authBarriersLock.RLock()
-			barrier, ok := authBarriers[proxyURL]
-			authBarriersLock.RUnlock()
 
-			if !ok {
-				barrier = base64.StdEncoding.EncodeToString([]byte(proxyURL.User.String()))
-				authBarriersLock.Lock()
-				authBarriers[proxyURL] = barrier
-				authBarriersLock.Unlock()
+		if proxyURL.User != nil {
+			authBarrierStorage := authHTTPStorage
+			if port == tlsPort {
+				authBarrierStorage = authHTTPSStorage
 			}
 
-			req += "Proxy-Authorization: Basic " + barrier + "\r\n"
+			auth := authBarrierStorage.Load()
+			if auth == nil {
+				authBarrier := base64.StdEncoding.EncodeToString([]byte(proxyURL.User.String()))
+				auth := &authBarrier
+				authBarrierStorage.Store(auth)
+			}
+
+			req += "Proxy-Authorization: Basic " + *auth.(*string) + "\r\n"
 		}
 		req += "\r\n"