diff --git a/include/mtl/string.hpp b/include/mtl/string.hpp
index 1d3f96f..f627048 100644
--- a/include/mtl/string.hpp
+++ b/include/mtl/string.hpp
@@ -156,6 +156,99 @@ public:
 
 	bool operator==(const string_view& rhs) const;
 	bool operator!=(const string_view& rhs) const;
+
+	/**
+	 * \brief Convert the signed integer to a string
+	 *
+	 * The value in str is overwritten.
+	 */
+	template <typename T, std::enable_if_t<std::is_signed_v<T>, bool> = true>
+	friend istring& to_string(T x, istring& str, bool hex = false) {
+		size_t num_char = 0;
+#ifdef __ARM_ARCH_4T__
+		if (hex) {
+			num_char = mtl_itostrx(x, str.data());
+		} else {
+			num_char = mtl_itostr(x, str.data());
+		}
+#else
+		itoa(x, str.data(), hex ? 16 : 10);
+		num_char = strlen(str.data());
+#endif
+		str.m_size = num_char;
+		return str;
+	}
+
+	/**
+	 * \brief Convert the unsigned integer to a string
+	 *
+	 * The value in str is overwritten.
+	 *
+	 * The template must check that the integer is not a boolean because
+	 * std::is_unsigned counts booleans as unsigned integers.
+	 */
+	template <typename T, std::enable_if_t<std::is_unsigned_v<T>
+	                      && !std::is_same_v<T, bool>, bool> = true>
+	friend istring& to_string(T x, istring& str, bool hex = false) {
+		size_t num_char = 0;
+#ifdef __ARM_ARCH_4T__
+		if (hex) {
+			num_char = mtl_utostrx(x, str.data());
+		} else {
+			num_char = mtl_utostr(x, str.data());
+		}
+#else
+		utoa(x, str.data(), hex ? 16 : 10);
+		num_char = strlen(str.data());
+#endif
+		str.m_size = num_char;
+		return str;
+	}
+
+	/**
+	 * \brief Convert the boolean to a string, using the provided buffer
+	 *
+	 * Writes the boolean as either "true" or "false". Depending on how
+	 * this function is used, `x ? "true" : "false"` may be faster.
+	 * Ex. mtl::string_stream does not use this function under the hood.
+	 *
+	 * The value in str is overwritten.
+	 *
+	 * This function needs to be templated otherwise non-boolean arguments
+	 * could be implicitly converted to boolean.
+	 */
+	template <typename T, std::enable_if_t<std::is_same_v<T, bool>, bool> = true>
+	friend istring& to_string(T x, istring& str) {
+		str = x ? "true" : "false";
+		return str;
+	}
+
+	/**
+	 * \brief Convert the address value to a string, using the provided buffer
+	 *
+	 * Always writes the address in hexidecimal format. Does not pad the
+	 * value to the address width.
+	 *
+	 * The value in str is overwritten.
+	 *
+	 * The template must check that the pointer is not a character pointer
+	 * otherwise C strings will be converted to their address string, not
+	 * the C string.
+	 */
+	template <typename T, std::enable_if_t<std::is_pointer_v<T>
+	                      && !std::is_same_v<T, char*>
+			      && !std::is_same_v<T, const char*>, bool> = true>
+	friend istring& to_string(T x, istring& str) {
+		size_t num_char = 0;
+#ifdef __ARM_ARCH_4T__
+		num_char = mtl_utostrx(reinterpret_cast<uint32_t>(x), str.data());
+#else
+		utoa(x, str.data(), 16);
+		num_char = strlen(str.data());
+#endif
+		str.m_size = num_char;
+		return str;
+	}
 };
 
 template <size_t C>
@@ -183,4 +276,5 @@ public:
 
 	using istring::operator=;
 };
+
 } // namespace ml