diff --git a/tox.ini b/tox.ini
index 198de646..b291092c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -39,7 +39,7 @@ deps =
     black==19.10b0
 
 commands =
-  black -v --check {toxinidir}/plugins {toxinidir}/tests
+  black -v --check --diff {toxinidir}/plugins {toxinidir}/tests
 
 [testenv:linters]
 deps =
@@ -48,7 +48,7 @@ deps =
     black==19.10b0
 
 commands =
-  black -v --check {toxinidir}/plugins {toxinidir}/tests
+  black -v --check --diff {toxinidir}/plugins {toxinidir}/tests
   yamllint -s {toxinidir}
   flake8 {toxinidir}