diff --git a/assets/src/bundles/browse/origin-search.js b/assets/src/bundles/browse/origin-search.js
--- a/assets/src/bundles/browse/origin-search.js
+++ b/assets/src/bundles/browse/origin-search.js
@@ -248,14 +248,15 @@
       event.preventDefault();
     });
 
-    const urlParams = new URLSearchParams(window.location.search);
-    const query = urlParams.get('q');
-    const withVisit = urlParams.has('with_visit');
-    const useSearchQL = urlParams.has('use_ql');
-    const withContent = urlParams.has('with_content');
-    const searchMetadata = urlParams.has('search_metadata');
-    const visitType = urlParams.get('visit_type');
-    if (query) {
+    if (window.location.search) {
+      const urlParams = new URLSearchParams(window.location.search);
+      const query = urlParams.get('q');
+      const withVisit = urlParams.has('with_visit');
+      const useSearchQL = urlParams.has('use_ql');
+      const withContent = urlParams.has('with_content');
+      const searchMetadata = urlParams.has('search_metadata');
+      const visitType = urlParams.get('visit_type');
+
       $('#swh-origins-url-patterns').val(query);
       $('#swh-search-origins-with-visit').prop('checked', withVisit);
       $('#swh-search-use-ql').prop('checked', useSearchQL ?? false);
diff --git a/cypress/integration/origin-search.spec.js b/cypress/integration/origin-search.spec.js
--- a/cypress/integration/origin-search.spec.js
+++ b/cypress/integration/origin-search.spec.js
@@ -266,6 +266,51 @@
 
   });
 
+  function checkSearchHasResults() {
+    cy.get('.swh-search-icon')
+        .click();
+
+    cy.wait('@checkOriginVisits');
+
+    cy.get('#origin-search-results')
+        .should('be.visible');
+
+    cy.get('tbody tr td.swh-origin-visit-type')
+      .should('exist');
+  }
+
+  it('should search all origins when no pattern is provided', function() {
+    cy.intercept('**/visit/latest/**').as('checkOriginVisits');
+
+    // with default filters
+    checkSearchHasResults();
+
+    // remove filters
+    cy.get('#swh-search-origins-with-visit')
+      .uncheck({force: true})
+      .get('#swh-filter-empty-visits')
+      .uncheck({force: true});
+    checkSearchHasResults();
+
+  });
+
+  it('should search all origins for a visit type', function() {
+    cy.intercept('**/visit/latest/**').as('checkOriginVisits');
+
+    for (const visitType of ['git', 'tar']) {
+      cy.get('#swh-search-visit-type')
+        .select(visitType);
+
+      checkSearchHasResults();
+
+      cy.get('tbody tr td.swh-origin-visit-type').then(elts => {
+        for (const elt of elts) {
+          cy.get(elt).should('have.text', visitType);
+        }
+      });
+    }
+  });
+
   context('Test pagination', function() {
     it('should not paginate if there are not many results', function() {
       // Setup search
diff --git a/swh/web/api/views/origin.py b/swh/web/api/views/origin.py
--- a/swh/web/api/views/origin.py
+++ b/swh/web/api/views/origin.py
@@ -161,7 +161,7 @@
 
 
 @api_route(
-    r"/origin/search/(?P<url_pattern>.+)/",
+    r"/origin/search/(?P<url_pattern>.*)/",
     "api-1-origin-search",
     throttle_scope="swh_api_origin_search",
 )
diff --git a/swh/web/templates/includes/origin-search-form.html b/swh/web/templates/includes/origin-search-form.html
--- a/swh/web/templates/includes/origin-search-form.html
+++ b/swh/web/templates/includes/origin-search-form.html
@@ -10,7 +10,7 @@
     <input class="form-control"
            placeholder="Enter a SWHID to resolve or string pattern(s) to search for in origin urls"
            type="text" id="swh-origins-url-patterns"
-           oninput="swh.webapp.validateSWHIDInput(this)" autofocus required>
+           oninput="swh.webapp.validateSWHIDInput(this)" autofocus>
     <div class="input-group-append">
       <button class="btn btn-primary" type="submit"><i class="swh-search-icon mdi mdi-24px mdi-magnify" aria-hidden="true"></i></button>
     </div>
diff --git a/swh/web/tests/api/views/test_origin.py b/swh/web/tests/api/views/test_origin.py
--- a/swh/web/tests/api/views/test_origin.py
+++ b/swh/web/tests/api/views/test_origin.py
@@ -793,3 +793,46 @@
 
     for obj in ["content", "origin", "release", "directory", "revision"]:
         assert counts.get(obj, 0) > 0
+
+
+@pytest.fixture
+def archived_origins(archive_data):
+    page_result = archive_data.origin_list(page_token=None, limit=10000)
+    origins = [origin.to_dict() for origin in page_result.results]
+    for origin in origins:
+        ovs = archive_data.origin_visit_get_with_statuses(origin["url"]).results
+        del origin["id"]
+        origin["type"] = ovs[0].visit.type
+
+    return origins
+
+
+def test_api_origin_search_empty_pattern(api_client, archived_origins):
+    url = reverse(
+        "api-1-origin-search",
+        url_args={"url_pattern": ""},
+        query_params={"limit": 10000},
+    )
+
+    rv = check_api_get_responses(api_client, url, status_code=200)
+
+    assert {o["url"] for o in rv.data} == {o["url"] for o in archived_origins}
+
+
+def test_api_origin_search_empty_pattern_and_visit_type(api_client, archived_origins):
+
+    visit_types = {o["type"] for o in archived_origins}
+
+    for visit_type in visit_types:
+
+        url = reverse(
+            "api-1-origin-search",
+            url_args={"url_pattern": ""},
+            query_params={"visit_type": visit_type, "limit": 10000},
+        )
+
+        rv = check_api_get_responses(api_client, url, status_code=200)
+
+        assert {o["url"] for o in rv.data} == {
+            o["url"] for o in archived_origins if o["type"] == visit_type
+        }