diff --git a/pyproject.toml b/pyproject.toml
index e63e2070..b1e865ce 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -35,7 +35,7 @@ jsonschema-markdown = "^0.3.13"
 lint = "ruff check"
 lint-fix = "ruff check --fix-only"
 format = "ruff format"
-format-check = "ruff format --check"
+format-check = "ruff format --check --diff"
 typecheck = "mypy tests/ abis_mapping/ docs/ scripts/"
 generate-instructions = "./scripts/generate_instructions.sh"
 generate-model-docs = "./scripts/generate_model_docs.sh"