diff --git a/src/util/index.js b/src/util/index.js
new file mode 100644
index 00000000..02d78b3d
--- /dev/null
+++ b/src/util/index.js
@@ -0,0 +1,41 @@
+import queryString from "query-string";
+import URI from "urijs";
+
+export const updateCategoricalQueryParams = (category, value) => {
+
+  let newURL;
+
+  /*
+    there are four cases
+    1. there are no query params
+    2. there are query params, but our category isn't there yet
+    3. there are query params and this is not the first entry to the given category
+    4. there are query params and ours already exists (remove it)
+  */
+
+  if (window.location.search === "") {
+    /* #1 */
+    newURL = `${window.location.href}?${queryString.stringify({category: [value]})}`
+    window.history.pushState("", "", newUrl)
+  } else {
+
+    const existingParams = queryString.parse(window.location.search);
+    const categoryAlreadyExists = existingParams[category];
+    const valueAlreadyExists = existingParams[category] && categoryAlreadyExists[value];
+
+    if (valueAlreadyExists) {
+      /* #4 (removal) */
+
+      newURL = `${window.location.href}?${queryString.stringify({category: [value]})}`
+    } else {
+      /* #3 */
+      existingParams
+    }
+
+  }
+
+}
+
+export const updateContinuousParams = (category, range) => {
+
+}