diff --git a/lib/http-axios.ts b/lib/http-axios.ts
index 1783be71..aa558e0a 100644
--- a/lib/http-axios.ts
+++ b/lib/http-axios.ts
@@ -7,6 +7,7 @@ import axios, {
 import { Readable } from "node:stream";
 import { HTTPError, ReadError, RequestError } from "./exceptions.js";
 import { USER_AGENT } from "./version.js";
+import { createURLSearchParams } from "./utils.js";
 
 interface httpClientConfig extends Partial<AxiosRequestConfig> {
   baseURL?: string;
@@ -86,12 +87,7 @@ export default class HTTPClient {
   }
 
   public async postForm<T>(url: string, body?: any): Promise<T> {
-    const params = new URLSearchParams();
-    for (const key in body) {
-      if (body.hasOwnProperty(key)) {
-        params.append(key, body[key]);
-      }
-    }
+    const params = body ? createURLSearchParams(body) : new URLSearchParams();
     const res = await this.instance.post(url, params.toString(), {
       headers: { "Content-Type": "application/x-www-form-urlencoded" },
     });
diff --git a/lib/http-fetch.ts b/lib/http-fetch.ts
index 257f975f..4e65efe3 100644
--- a/lib/http-fetch.ts
+++ b/lib/http-fetch.ts
@@ -2,6 +2,7 @@ import { Buffer } from "node:buffer";
 import { Readable } from "node:stream";
 import { HTTPFetchError } from "./exceptions.js";
 import { USER_AGENT } from "./version.js";
+import { createURLSearchParams } from "./utils.js";
 
 export interface FetchRequestConfig {
   headers?: Record<string, string>;
@@ -63,12 +64,7 @@ export default class HTTPFetchClient {
   public async get<T>(url: string, params?: any): Promise<Response> {
     const requestUrl = new URL(url, this.baseURL);
     if (params) {
-      const searchParams = new URLSearchParams();
-      for (const key in params) {
-        if (params.hasOwnProperty(key)) {
-          searchParams.append(key, params[key]);
-        }
-      }
+      const searchParams = createURLSearchParams(params);
       requestUrl.search = searchParams.toString();
     }
     const response = await fetch(requestUrl, {
@@ -118,12 +114,7 @@ export default class HTTPFetchClient {
 
   public async postForm(url: string, body?: any): Promise<Response> {
     const requestUrl = new URL(url, this.baseURL);
-    const params = new URLSearchParams();
-    for (const key in body) {
-      if (body.hasOwnProperty(key)) {
-        params.append(key, body[key]);
-      }
-    }
+    const params = body ? createURLSearchParams(body) : new URLSearchParams();
     const response = await fetch(requestUrl, {
       method: "POST",
       headers: {
@@ -186,7 +177,8 @@ export default class HTTPFetchClient {
   public async delete(url: string, params?: any): Promise<Response> {
     const requestUrl = new URL(url, this.baseURL);
     if (params) {
-      requestUrl.search = new URLSearchParams(params).toString();
+      const searchParams = createURLSearchParams(params);
+      requestUrl.search = searchParams.toString();
     }
     const response = await fetch(requestUrl, {
       method: "DELETE",
diff --git a/lib/utils.ts b/lib/utils.ts
index d3e29903..1569bd17 100644
--- a/lib/utils.ts
+++ b/lib/utils.ts
@@ -25,6 +25,18 @@ function toArrayBuffer(input: Uint8Array | Buffer): ArrayBuffer {
   return arrayBuffer;
 }
 
+export function createURLSearchParams(
+  params: Record<string, unknown>,
+): URLSearchParams {
+  const searchParams = new URLSearchParams();
+  for (const [key, value] of Object.entries(params)) {
+    if (value != null) {
+      searchParams.append(key, String(value));
+    }
+  }
+  return searchParams;
+}
+
 export function createMultipartFormData(
   this: FormData | void,
   formBody: Record<string, any>,
diff --git a/test/utils.spec.ts b/test/utils.spec.ts
index 0028d620..5af92925 100644
--- a/test/utils.spec.ts
+++ b/test/utils.spec.ts
@@ -1,4 +1,4 @@
-import { ensureJSON } from "../lib/utils.js";
+import { ensureJSON, createURLSearchParams } from "../lib/utils.js";
 import { JSONParseError } from "../lib/exceptions.js";
 import { equal, ok } from "node:assert";
 
@@ -19,4 +19,69 @@ describe("utils", () => {
       }
     });
   });
+
+  describe("createURLSearchParams", () => {
+    it("creates URLSearchParams from object with string values", () => {
+      const params = { key1: "value1", key2: "value2" };
+      const result = createURLSearchParams(params);
+      equal(result.get("key1"), "value1");
+      equal(result.get("key2"), "value2");
+    });
+
+    it("converts number values to strings", () => {
+      const params = { num: 123, float: 45.67 };
+      const result = createURLSearchParams(params);
+      equal(result.get("num"), "123");
+      equal(result.get("float"), "45.67");
+    });
+
+    it("converts boolean values to strings", () => {
+      const params = { bool1: true, bool2: false };
+      const result = createURLSearchParams(params);
+      equal(result.get("bool1"), "true");
+      equal(result.get("bool2"), "false");
+    });
+
+    it("filters out null values", () => {
+      const params = { key1: "value1", key2: null, key3: "value3" };
+      const result = createURLSearchParams(params);
+      equal(result.get("key1"), "value1");
+      equal(result.get("key2"), null);
+      equal(result.get("key3"), "value3");
+    });
+
+    it("filters out undefined values", () => {
+      const params = { key1: "value1", key2: undefined, key3: "value3" };
+      const result = createURLSearchParams(params);
+      equal(result.get("key1"), "value1");
+      equal(result.get("key2"), null);
+      equal(result.get("key3"), "value3");
+    });
+
+    it("handles empty object", () => {
+      const params = {};
+      const result = createURLSearchParams(params);
+      equal(result.toString(), "");
+    });
+
+    it("handles mixed types and null/undefined", () => {
+      const params = {
+        str: "test",
+        num: 42,
+        bool: true,
+        nullVal: null,
+        undefinedVal: undefined,
+        zero: 0,
+        emptyStr: "",
+      };
+      const result = createURLSearchParams(params);
+      equal(result.get("str"), "test");
+      equal(result.get("num"), "42");
+      equal(result.get("bool"), "true");
+      equal(result.get("zero"), "0");
+      equal(result.get("emptyStr"), "");
+      equal(result.get("nullVal"), null);
+      equal(result.get("undefinedVal"), null);
+    });
+  });
 });