diff --git a/Gemfile b/Gemfile
index 89f216c..bfb196c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,4 +10,5 @@ group :development do
     gem 'minitest-reporters'
     gem 'rake'
     gem 'rubocop'
+    gem 'webmock'
 end
diff --git a/test/ipinfo_test.rb b/test/ipinfo_test.rb
index 5663d7c..3478c28 100644
--- a/test/ipinfo_test.rb
+++ b/test/ipinfo_test.rb
@@ -177,20 +177,41 @@ def test_lookup_ip4
     end
 
     def test_resproxy
-        ipinfo = IPinfo.create(ENV['IPINFO_TOKEN'])
+        # Mock the resproxy API response (with any query params)
+        stub_request(:get, /https:\/\/ipinfo\.io\/resproxy\/#{TEST_RESPROXY_IP}/)
+            .to_return(
+                status: 200,
+                body: {
+                    ip: TEST_RESPROXY_IP,
+                    last_seen: '2025-01-20',
+                    percent_days_seen: 0.85,
+                    service: 'example_service'
+                }.to_json,
+                headers: { 'Content-Type' => 'application/json' }
+            )
+
+        ipinfo = IPinfo.create('test_token')
 
         # multiple checks for cache
         (0...5).each do |_|
             resp = ipinfo.resproxy(TEST_RESPROXY_IP)
             assert_equal(resp.ip, TEST_RESPROXY_IP)
-            refute_nil(resp.last_seen)
-            refute_nil(resp.percent_days_seen)
-            refute_nil(resp.service)
+            assert_equal(resp.last_seen, '2025-01-20')
+            assert_equal(resp.percent_days_seen, 0.85)
+            assert_equal(resp.service, 'example_service')
         end
     end
 
     def test_resproxy_empty
-        ipinfo = IPinfo.create(ENV['IPINFO_TOKEN'])
+        # Mock the resproxy API response for non-residential proxy IP (with any query params)
+        stub_request(:get, /https:\/\/ipinfo\.io\/resproxy\/#{TEST_IPV4}/)
+            .to_return(
+                status: 200,
+                body: '{}',
+                headers: { 'Content-Type' => 'application/json' }
+            )
+
+        ipinfo = IPinfo.create('test_token')
 
         resp = ipinfo.resproxy(TEST_IPV4)
         assert_equal(resp.all, {})
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 20c5fb4..0b7aaf3 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -8,6 +8,10 @@
 
 require 'minitest/autorun'
 require 'minitest/reporters'
+require 'webmock/minitest'
+
+# Allow real network connections by default, but tests can disable this
+WebMock.allow_net_connect!
 
 Minitest::Reporters.use!(
     Minitest::Reporters::SpecReporter.new