diff --git a/main.go b/main.go
index b76eee6..0e502d5 100644
--- a/main.go
+++ b/main.go
@@ -1,12 +1,14 @@
 package main
 
 import (
+	"bufio"
 	"crypto/x509"
 	"encoding/hex"
 	"encoding/pem"
 	"fmt"
 	"io/ioutil"
 	"os"
+	"strings"
 
 	"golang.org/x/crypto/pkcs12"
 	"gopkg.in/alecthomas/kingpin.v2"
@@ -17,7 +19,7 @@ var (
 
 	dump     = app.Command("dump", "Display information about a certificate.")
 	dumpFile = dump.Arg("file", "Certificate file to dump.").Required().String()
-	dumpType = dump.Flag("format", "Format of given input. If unspecified, certigo guesses based on file extension").Short('f').String()
+	dumpType = dump.Flag("format", "Format of given input. If unspecified, certigo guesses based on file extension").Default("guess").Short('f').String()
 )
 
 func main() {
@@ -51,11 +53,28 @@ func getCerts(file, format string) ([]*x509.Certificate, error) {
 			block, data = pem.Decode(data)
 		}
 	case "PKCS12":
-		_, cert, err := pkcs12.Decode(data, "password")
+		scanner := bufio.NewReader(os.Stdin)
+		fmt.Print("Enter password: ")
+		password, _ := scanner.ReadString('\n')
+		blocks, err := pkcs12.ToPEM(data, strings.TrimSuffix(password, "\n"))
 		if err != nil {
 			return nil, err
 		}
-		certs = append(certs, cert)
+		for _, block := range blocks {
+			cert, err := x509.ParseCertificates(block.Bytes)
+			if err != nil {
+				return nil, err
+			}
+			certs = append(certs, cert[0])
+		}
+	case "guess":
+		if strings.HasSuffix(file, "pem") {
+			return getCerts(file, "PEM")
+		} else if strings.HasSuffix(file, "p12") || strings.HasSuffix(file, "pks") {
+			return getCerts(file, "PKCS12")
+		} else {
+			return getCerts(file, ", couldn't guess format")
+		}
 	default:
 		return nil, fmt.Errorf("unknown type %s", format)
 	}