diff --git a/documentation/Makefile b/documentation/Makefile
index 65e29713d4..07801cc2d3 100644
--- a/documentation/Makefile
+++ b/documentation/Makefile
@@ -43,11 +43,11 @@ PNGs := $(foreach dir, $(IMAGEDIRS), $(patsubst %.svg,%.png,$(wildcard $(SOURCED
 
 # Pattern rule for converting SVG to PDF
 %.pdf : %.svg
-	$(SVG2PDF) --format=Pdf --output=$@ $<
+	$(SVG2PDF) --format=pdf --output=$@ $<
 
 # Pattern rule for converting SVG to PNG
 %.png : %.svg
-	$(SVG2PNG) --format=Png --output=$@ $<
+	$(SVG2PNG) --format=png --output=$@ $<
 
 clean:
 	@rm -rf $(BUILDDIR) $(PNGs) $(PDFs) poky.yaml sphinx-static/switchers.js releases.rst