diff --git a/lib/httparrot/p_handler.ex b/lib/httparrot/p_handler.ex
index f47c622..cc66aca 100644
--- a/lib/httparrot/p_handler.ex
+++ b/lib/httparrot/p_handler.ex
@@ -18,9 +18,9 @@ defmodule HTTParrot.PHandler do
   end
 
   def content_types_accepted(req, state) do
-    {[{{"application", "json", :*}, :post_json},
-      {{"application", "octet-stream", :*}, :post_json},
-      {{"text", "plain", :*}, :post_json},
+    {[{{"application", "json", :*}, :post_binary},
+      {{"application", "octet-stream", :*}, :post_binary},
+      {{"text", "plain", :*}, :post_binary},
       {{"application", "x-www-form-urlencoded", :*}, :post_form}], req, state}
   end
 
@@ -33,12 +33,18 @@ defmodule HTTParrot.PHandler do
     post(req, [form: body, data: "", json: nil])
   end
 
-  def post_json(req, _state) do
+  def post_binary(req, _state) do
     {:ok, body, req} = :cowboy_req.body(req)
-    if JSEX.is_json?(body) do
-      post(req, [form: [{}], data: body, json: JSEX.decode!(body)])
+    if String.valid?(body) do
+      if JSEX.is_json?(body) do
+        post(req, [form: [{}], data: body, json: JSEX.decode!(body)])
+      else
+        post(req, [form: [{}], data: body, json: nil])
+      end
     else
-      post(req, [form: [{}], data: body, json: nil])
+      # Octet-stream
+      body = :base64.encode(body)
+      post(req, [form: [{}], data: "data:application/octet-stream;base64," <> body, json: nil])
     end
   end
 
diff --git a/test/p_handler_test.exs b/test/p_handler_test.exs
index ced7201..ae76932 100644
--- a/test/p_handler_test.exs
+++ b/test/p_handler_test.exs
@@ -39,26 +39,38 @@ defmodule HTTParrot.PHandlerTest do
   end
 
   test "returns json with general info and P[OST, ATCH, UT] JSON body data" do
-    expect(:cowboy_req, :body, 1, {:ok, :body, :req2})
+    expect(:cowboy_req, :body, 1, {:ok, "body", :req2})
     expect(:cowboy_req, :set_resp_body, [{[:response, :req3], :req4}])
     expect(HTTParrot.GeneralRequestInfo, :retrieve, 1, {[:info], :req3})
     expect(JSEX, :is_json?, 1, true)
     expect(JSEX, :decode!, 1, :decoded_json)
-    expect(JSEX, :encode!, [{[[:info, {:form, [{}]}, {:data, :body}, {:json, :decoded_json}]], :response}])
+    expect(JSEX, :encode!, [{[[:info, {:form, [{}]}, {:data, "body"}, {:json, :decoded_json}]], :response}])
 
-    assert post_json(:req1, :state) == {true, :req4, nil}
+    assert post_binary(:req1, :state) == {true, :req4, nil}
 
     assert validate HTTParrot.GeneralRequestInfo
   end
 
   test "returns json with general info and P[OST, ATCH, UT] non-JSON body data" do
-    expect(:cowboy_req, :body, 1, {:ok, :body, :req2})
+    expect(:cowboy_req, :body, 1, {:ok, "body", :req2})
     expect(:cowboy_req, :set_resp_body, [{[:response, :req3], :req4}])
     expect(HTTParrot.GeneralRequestInfo, :retrieve, 1, {[:info], :req3})
     expect(JSEX, :is_json?, 1, false)
-    expect(JSEX, :encode!, [{[[:info, {:form, [{}]}, {:data, :body}, {:json, nil}]], :response}])
+    expect(JSEX, :encode!, [{[[:info, {:form, [{}]}, {:data, "body"}, {:json, nil}]], :response}])
 
-    assert post_json(:req1, :state) == {true, :req4, nil}
+    assert post_binary(:req1, :state) == {true, :req4, nil}
+
+    assert validate HTTParrot.GeneralRequestInfo
+  end
+
+  test "returns json with general info and P[OST, ATCH, UT] octet-stream body data" do
+    expect(:cowboy_req, :body, 1, {:ok, <<0xffff :: 16>>, :req2})
+    expect(:cowboy_req, :set_resp_body, [{[:response, :req3], :req4}])
+    expect(HTTParrot.GeneralRequestInfo, :retrieve, 1, {[:info], :req3})
+    expect(JSEX, :is_json?, 1, false)
+    expect(JSEX, :encode!, [{[[:info, {:form, [{}]}, {:data, "data:application/octet-stream;base64,//8="}, {:json, nil}]], :response}])
+
+    assert post_binary(:req1, :state) == {true, :req4, nil}
 
     assert validate HTTParrot.GeneralRequestInfo
   end