diff --git a/README.md b/README.md
index 34b5b1d..99edce4 100644
--- a/README.md
+++ b/README.md
@@ -267,6 +267,7 @@ These environment variables allow setting default config values, but can be over
 | WHOOGLE_CONFIG_COUNTRY         | Filter results by hosting country                               |
 | WHOOGLE_CONFIG_LANGUAGE        | Set interface language                                          |
 | WHOOGLE_CONFIG_SEARCH_LANGUAGE | Set search result language                                      |
+| WHOOGLE_CONFIG_BLOCK           | Block websites from search results (use comma-separated list)   |
 | WHOOGLE_CONFIG_DARK            | Enable dark theme                                               |
 | WHOOGLE_CONFIG_SAFE            | Enable safe searches                                            |
 | WHOOGLE_CONFIG_ALTS            | Use social media site alternatives (nitter, invidious, etc)     |
diff --git a/app.json b/app.json
index 6889e5b..691f8fc 100644
--- a/app.json
+++ b/app.json
@@ -85,6 +85,11 @@
         "value": "",
         "required": false
     },
+    "WHOOGLE_CONFIG_BLOCK": {
+        "description": "[CONFIG] Block websites from search results (comma-separated list)",
+        "value": "",
+        "required": false
+    },
     "WHOOGLE_CONFIG_DARK": {
         "description": "[CONFIG] Enable dark mode (set to 1 or leave blank)",
         "value": "",
diff --git a/app/models/config.py b/app/models/config.py
index 84ad0e4..3898ae7 100644
--- a/app/models/config.py
+++ b/app/models/config.py
@@ -18,6 +18,7 @@ class Config:
             'WHOOGLE_CONFIG_STYLE',
             open(os.path.join(app_config['STATIC_FOLDER'],
                               'css/variables.css')).read())
+        self.block = os.getenv('WHOOGLE_CONFIG_BLOCK', '')
         self.ctry = os.getenv('WHOOGLE_CONFIG_COUNTRY', '')
         self.safe = read_config_bool('WHOOGLE_CONFIG_SAFE')
         self.dark = read_config_bool('WHOOGLE_CONFIG_DARK')
diff --git a/app/request.py b/app/request.py
index b4c67dd..6fabe46 100644
--- a/app/request.py
+++ b/app/request.py
@@ -120,6 +120,10 @@ def gen_query(query, args, config, near_city=None) -> str:
     ) if config.lang_interface else ''
     param_dict['safe'] = '&safe=' + ('active' if config.safe else 'off')
 
+    # Block all sites specified in the user config
+    for blocked in config.block.split(','):
+        query += (' -site:' + blocked) if blocked else ''
+
     for val in param_dict.values():
         if not val:
             continue
diff --git a/app/routes.py b/app/routes.py
index 053cb72..7867442 100644
--- a/app/routes.py
+++ b/app/routes.py
@@ -2,7 +2,6 @@ import argparse
 import base64
 import io
 import json
-import os
 import pickle
 import urllib.parse as urlparse
 import uuid
@@ -17,7 +16,7 @@ from app import app
 from app.models.config import Config
 from app.request import Request, TorError
 from app.utils.bangs import resolve_bang
-from app.utils.session import valid_user_session
+from app.utils.session import generate_user_key, valid_user_session
 from app.utils.search import *
 
 # Load DDG bang json files only on init
diff --git a/app/templates/header.html b/app/templates/header.html
index 4eb7822..b353d92 100644
--- a/app/templates/header.html
+++ b/app/templates/header.html
@@ -22,7 +22,7 @@
                             style="background-color: {{ 'var(--whoogle-dark-result-bg)' if config.dark else 'var(--whoogle-result-bg)' }} !important;
                                    color: {{ 'var(--whoogle-dark-text)' if config.dark else 'var(--whoogle-text)' }};
                             type="text" 
-                            value="{{ query }}">
+                            value="{{ query[:query.find('-site:')] }}">
                         <input style="color: {{ 'var(--whoogle-dark-text)' if config.dark else 'var(--whoogle-text)' }}" id="search-reset" type="reset" value="x">
                         <input name="tbm" value="{{ search_type }}" style="display: none">
                         <input type="submit" style="display: none;">
@@ -54,7 +54,7 @@
                             name="q"
                             spellcheck="false"
                             type="text"
-                            value="{{ query }}"
+                            value="{{ query[:query.find('-site:')] }}"
                             style="background-color: {{ 'var(--whoogle-dark-result-bg)' if config.dark else 'var(--whoogle-result-bg)' }} !important;
                                    color: {{ 'var(--whoogle-dark-text)' if config.dark else 'var(--whoogle-text)' }};
                                    border-bottom: {{ '2px solid var(--whoogle-dark-element-bg)' if config.dark else '0px' }};">
diff --git a/app/templates/index.html b/app/templates/index.html
index 3625719..9d43988 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -106,6 +106,10 @@
 				    <label for="config-near">Near: </label>
 				    <input type="text" name="near" id="config-near" placeholder="City Name" value="{{ config.near }}">
 				</div>
+                <div class="config-div config-div-block">
+                    <label for="config-block">Block: </label>
+                    <input type="text" name="block" id="config-block" placeholder="Comma-separated site list" value="{{ config.block }}">
+                </div>
 				<div class="config-div config-div-nojs">
 				    <label for="config-nojs">Show NoJS Links: </label>
 				    <input type="checkbox" name="nojs" id="config-nojs" {{ 'checked' if config.nojs else '' }}>
diff --git a/app/utils/search.py b/app/utils/search.py
index b71e6dd..a856bf6 100644
--- a/app/utils/search.py
+++ b/app/utils/search.py
@@ -1,5 +1,4 @@
 from app.filter import Filter, get_first_link
-from app.utils.session import generate_user_key
 from app.request import gen_query
 from bs4 import BeautifulSoup as bsoup
 from cryptography.fernet import Fernet, InvalidToken
diff --git a/test/test_results.py b/test/test_results.py
index 38b9936..ff6fe4b 100644
--- a/test/test_results.py
+++ b/test/test_results.py
@@ -3,6 +3,9 @@ from app.filter import Filter
 from app.utils.session import generate_user_key
 from datetime import datetime
 from dateutil.parser import *
+from urllib.parse import urlparse
+
+from test.conftest import demo_config
 
 
 def get_search_results(data):
@@ -46,6 +49,29 @@ def test_post_results(client):
     assert len(get_search_results(rv.data)) <= 15
 
 
+def test_block_results(client):
+    rv = client.post('/search', data=dict(q='pinterest'))
+    assert rv._status_code == 200
+
+    has_pinterest = False
+    for link in BeautifulSoup(rv.data, 'html.parser').find_all('a', href=True):
+        if 'pinterest.com' in urlparse(link['href']).netloc:
+            has_pinterest = True
+            break
+
+    assert has_pinterest
+
+    demo_config['block'] = 'pinterest.com'
+    rv = client.post('/config', data=demo_config)
+    assert rv._status_code == 302
+
+    rv = client.post('/search', data=dict(q='pinterest'))
+    assert rv._status_code == 200
+
+    for link in BeautifulSoup(rv.data, 'html.parser').find_all('a', href=True):
+        assert 'pinterest.com' not in urlparse(link['href']).netloc
+
+
 # TODO: Unit test the site alt method instead -- the results returned
 # are too unreliable for this test in particular.
 # def test_site_alts(client):
diff --git a/whoogle.env b/whoogle.env
index 0ee372f..3a0f88b 100644
--- a/whoogle.env
+++ b/whoogle.env
@@ -18,25 +18,39 @@
 
 # See app/static/settings/countries.json for values
 #WHOOGLE_CONFIG_COUNTRY=countryUK
+
 # See app/static/settings/languages.json for values
 #WHOOGLE_CONFIG_LANGUAGE=lang_en
+
 # See app/static/settings/languages.json for values
 #WHOOGLE_CONFIG_SEARCH_LANGUAGE=lang_en
+
 # Disable changing of config from client
 #WHOOGLE_CONFIG_DISABLE=1
+
+# Block websites from search results (comma-separated list)
+#WHOOGLE_CONFIG_BLOCK=pinterest.com,whitehouse.gov
+
 # Dark mode
 #WHOOGLE_CONFIG_DARK=1
+
 # Safe search mode
 #WHOOGLE_CONFIG_SAFE=1
+
 # Use social media site alternatives (nitter, bibliogram, etc)
 #WHOOGLE_CONFIG_ALTS=1
+
 # Use Tor if available
 #WHOOGLE_CONFIG_TOR=1
+
 # Open results in new tab
 #WHOOGLE_CONFIG_NEW_TAB=1
+
 # Search using GET requests only (exposes query in logs)
 #WHOOGLE_CONFIG_GET_ONLY=1
+
 # Set instance URL
 #WHOOGLE_CONFIG_URL=https://<whoogle url>/
+
 # Set custom CSS styling/theming
 #WHOOGLE_CONFIG_STYLE=":root { /* LIGHT THEME COLORS */ --whoogle-background: #d8dee9; --whoogle-accent: #2e3440; --whoogle-text: #3B4252; --whoogle-contrast-text: #eceff4; --whoogle-secondary-text: #70757a; --whoogle-result-bg: #fff; --whoogle-result-title: #4c566a; --whoogle-result-url: #81a1c1; --whoogle-result-visited: #a3be8c; /* DARK THEME COLORS */ --whoogle-dark-background: #222; --whoogle-dark-accent: #685e79; --whoogle-dark-text: #fff; --whoogle-dark-contrast-text: #000; --whoogle-dark-secondary-text: #bbb; --whoogle-dark-result-bg: #000; --whoogle-dark-result-title: #1967d2; --whoogle-dark-result-url: #4b11a8; --whoogle-dark-result-visited: #bbbbff; }"