diff --git a/src/RequestBody.php b/src/RequestBody.php
index 34eac82a..06f9810a 100644
--- a/src/RequestBody.php
+++ b/src/RequestBody.php
@@ -19,7 +19,7 @@
  *
  * @implements \IteratorAggregate<int, string>
  */
-final class RequestBody implements ReadableStream, \IteratorAggregate
+final class RequestBody implements ReadableStream, \IteratorAggregate, \Stringable
 {
     use ReadableStreamIteratorAggregate;
 
@@ -46,8 +46,7 @@ public function read(?Cancellation $cancellation = null): ?string
 
     /**
      * @see Payload::buffer()
-     * @throws ClientException
-     * @throws BufferException|StreamException
+     * @throws ClientException|BufferException|StreamException
      */
     public function buffer(?Cancellation $cancellation = null, int $limit = \PHP_INT_MAX): string
     {
@@ -88,4 +87,15 @@ public function increaseSizeLimit(int $size): void
 
         ($this->upgradeSize)($size);
     }
+
+    /**
+     * Buffers entire stream before returning. Use {@see self::buffer()} to optionally provide a {@see Cancellation}
+     * and/or length limit.
+     *
+     * @throws ClientException|BufferException|StreamException
+     */
+    public function __toString(): string
+    {
+        return $this->buffer();
+    }
 }
diff --git a/test/RequestBodyTest.php b/test/RequestBodyTest.php
index db8aef82..63e60e70 100644
--- a/test/RequestBodyTest.php
+++ b/test/RequestBodyTest.php
@@ -12,6 +12,6 @@ public function testIncreaseWithoutCallback(): void
     {
         $body = new RequestBody(new ReadableBuffer("foobar"));
         $body->increaseSizeLimit(1);
-        $this->assertSame("foobar", $body->buffer());
+        $this->assertSame("foobar", (string) $body);
     }
 }