diff --git a/tests/test_cdx_utils.py b/tests/test_cdx_utils.py
new file mode 100644
index 0000000..27435f2
--- /dev/null
+++ b/tests/test_cdx_utils.py
@@ -0,0 +1,99 @@
+import pytest
+from waybackpy.exceptions import WaybackError
+from waybackpy.cdx_utils import (
+    get_total_pages,
+    full_url,
+    get_response,
+    check_filters,
+    check_collapses,
+    check_match_type,
+)
+
+
+def test_get_total_pages():
+    url = "twitter.com"
+    user_agent = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.2 Safari/605.1.15"
+    assert get_total_pages(url=url, user_agent=user_agent) >= 56
+
+
+def test_full_url():
+    params = {}
+    endpoint = "https://web.archive.org/cdx/search/cdx"
+    assert endpoint == full_url(endpoint, params)
+
+    params = {"a": "1"}
+    assert "https://web.archive.org/cdx/search/cdx?a=1" == full_url(endpoint, params)
+    assert "https://web.archive.org/cdx/search/cdx?a=1" == full_url(
+        endpoint + "?", params
+    )
+
+    params["b"] = 2
+    assert "https://web.archive.org/cdx/search/cdx?a=1&b=2" == full_url(
+        endpoint + "?", params
+    )
+
+    params["c"] = "foo bar"
+    assert "https://web.archive.org/cdx/search/cdx?a=1&b=2&c=foo%20bar" == full_url(
+        endpoint + "?", params
+    )
+
+
+def test_get_response():
+    url = "https://github.com"
+    user_agent = (
+        "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:78.0) Gecko/20100101 Firefox/78.0"
+    )
+    headers = {"User-Agent": "%s" % user_agent}
+    response = get_response(url, headers=headers)
+    assert response.status_code == 200
+
+    url = "http/wwhfhfvhvjhmom"
+    with pytest.raises(WaybackError):
+        get_response(url, headers=headers)
+
+
+def test_check_filters():
+    filters = []
+    check_filters(filters)
+
+    filters = ["statuscode:200", "timestamp:20215678901234", "original:https://url.com"]
+    check_filters(filters)
+
+    with pytest.raises(WaybackError):
+        check_filters("not-list")
+
+    with pytest.raises(WaybackError):
+        check_filters(["invalid"])
+
+
+def test_check_collapses():
+    collapses = []
+    check_collapses(collapses)
+
+    collapses = ["timestamp:10"]
+    check_collapses(collapses)
+
+    collapses = ["urlkey"]
+    check_collapses(collapses)
+
+    collapses = "urlkey"  # NOT LIST
+    with pytest.raises(WaybackError):
+        check_collapses(collapses)
+
+    collapses = ["also illegal collapse"]
+    with pytest.raises(WaybackError):
+        check_collapses(collapses)
+
+
+def test_check_match_type():
+    assert None == check_match_type(None, "url")
+    match_type = "exact"
+    url = "test_url"
+    assert None == check_match_type(match_type, url)
+
+    url = "has * in it"
+    with pytest.raises(WaybackError):
+        check_match_type("domain", url)
+
+    with pytest.raises(WaybackError):
+        check_match_type("not a valid type", "url")