diff --git a/cmd/constant.go b/cmd/constant.go
index daacf6fa..8b94dc2c 100644
--- a/cmd/constant.go
+++ b/cmd/constant.go
@@ -8,7 +8,7 @@ var writeInplace = false
 var outputToJSON = false
 var outputFormat = "yaml"
 var inputFormatDefault = "yaml"
-var inputFormat = "" // default to "" so that we can (lazily) detect inputFormat from input filename
+var inputFormat = ""
 
 var exitStatus = false
 var forceColor = false
diff --git a/cmd/root.go b/cmd/root.go
index d832aca2..76782ccb 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -85,7 +85,7 @@ yq -P sample.json
 	}
 
 	rootCmd.PersistentFlags().StringVarP(&outputFormat, "output-format", "o", "yaml", "[yaml|y|json|j|props|p|xml|x] output format type.")
-	rootCmd.PersistentFlags().StringVarP(&inputFormat, "input-format", "p", "", "[yaml|y|props|p|xml|x] parse format for input. Note that json is a subset of yaml.") // use "" as default instead of "yaml", to be able to detect from input filename
+	rootCmd.PersistentFlags().StringVarP(&inputFormat, "input-format", "p", "", "[yaml|y|props|p|xml|x] parse format for input. Note that json is a subset of yaml.")
 
 	rootCmd.PersistentFlags().StringVar(&yqlib.ConfiguredXMLPreferences.AttributePrefix, "xml-attribute-prefix", yqlib.ConfiguredXMLPreferences.AttributePrefix, "prefix for xml attributes")
 	rootCmd.PersistentFlags().StringVar(&yqlib.ConfiguredXMLPreferences.ContentName, "xml-content-name", yqlib.ConfiguredXMLPreferences.ContentName, "name for xml content (if no attribute name is present).")
diff --git a/cmd/utils.go b/cmd/utils.go
index 3da4de41..cc20a827 100644
--- a/cmd/utils.go
+++ b/cmd/utils.go
@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"strings"
 
 	"github.com/mikefarah/yq/v4/pkg/yqlib"
 	"github.com/spf13/cobra"
@@ -58,13 +57,10 @@ func initCommand(cmd *cobra.Command, args []string) (string, []string, error) {
 }
 
 func configureDecoder(evaluateTogether bool, inputFilename string) (yqlib.Decoder, error) {
-	if inputFormat == "" && inputFilename != "" {
-		nPos := strings.LastIndex(inputFilename, ".")
-		if nPos > -1 {
-			inputFormat = inputFilename[nPos+1:]
-		} else {
-			inputFormat = inputFormatDefault
-		}
+	if inputFormat == "" {
+		inputFormat = yqlib.InputFormatFromFilename(inputFilename, inputFormatDefault)
+	} else {
+		yqlib.GetLogger().Debugf("user specified inputFormat '%s'", inputFormat)
 	}
 	yqlibInputFormat, err := yqlib.InputFormatFromString(inputFormat)
 	if err != nil {
diff --git a/pkg/yqlib/decoder.go b/pkg/yqlib/decoder.go
index dbc1d768..c06a5a72 100644
--- a/pkg/yqlib/decoder.go
+++ b/pkg/yqlib/decoder.go
@@ -3,6 +3,7 @@ package yqlib
 import (
 	"fmt"
 	"io"
+	"strings"
 )
 
 type InputFormat uint
@@ -29,7 +30,7 @@ func InputFormatFromString(format string) (InputFormat, error) {
 		return YamlInputFormat, nil
 	case "xml", "x":
 		return XMLInputFormat, nil
-	case "props", "p":
+	case "properties", "props", "p":
 		return PropertiesInputFormat, nil
 	case "json", "ndjson", "j":
 		return JsonInputFormat, nil
@@ -41,3 +42,18 @@ func InputFormatFromString(format string) (InputFormat, error) {
 		return 0, fmt.Errorf("unknown format '%v' please use [yaml|xml|props]", format)
 	}
 }
+
+func InputFormatFromFilename(filename string, defaultFormat string) string {
+	if filename != "" {
+		GetLogger().Debugf("checking filename '%s' for inputFormat", filename)
+		nPos := strings.LastIndex(filename, ".")
+		if nPos > -1 {
+			inputFormat := filename[nPos+1:]
+			GetLogger().Debugf("detected inputFormat '%s'", inputFormat)
+			return inputFormat
+		}
+	}
+
+	GetLogger().Debugf("using default inputFormat '%s'", defaultFormat)
+	return defaultFormat
+}