diff --git a/format/text/encoding.go b/format/text/encoding.go
index ffaa0070..05f82d21 100644
--- a/format/text/encoding.go
+++ b/format/text/encoding.go
@@ -31,7 +31,7 @@ func init() {
 		}
 		return bb
 	})
-	interp.RegisterFunc0("to_hex", func(_ *interp.Interp, c string) any {
+	interp.RegisterFunc0("to_hex", func(_ *interp.Interp, c any) any {
 		br, err := interp.ToBitReader(c)
 		if err != nil {
 			return err
@@ -73,7 +73,7 @@ func init() {
 	type toBase64Opts struct {
 		Encoding string
 	}
-	interp.RegisterFunc1("_to_base64", func(_ *interp.Interp, c string, opts toBase64Opts) any {
+	interp.RegisterFunc1("_to_base64", func(_ *interp.Interp, c any, opts toBase64Opts) any {
 		br, err := interp.ToBitReader(c)
 		if err != nil {
 			return err
diff --git a/format/text/testdata/random.bin.gz b/format/text/testdata/random.bin.gz
new file mode 100644
index 00000000..3aa3a1ef
Binary files /dev/null and b/format/text/testdata/random.bin.gz differ
diff --git a/format/text/testdata/to_base64.fqtest b/format/text/testdata/to_base64.fqtest
new file mode 100644
index 00000000..c8d2b3d5
--- /dev/null
+++ b/format/text/testdata/to_base64.fqtest
@@ -0,0 +1,2 @@
+$ fq '.uncompressed | to_base64' random.bin.gz -r
+8Vr6cUH6erA=
diff --git a/format/text/testdata/to_hex.fqtest b/format/text/testdata/to_hex.fqtest
new file mode 100644
index 00000000..356a1f80
--- /dev/null
+++ b/format/text/testdata/to_hex.fqtest
@@ -0,0 +1,2 @@
+$ fq '.uncompressed | tohex' random.bin.gz -r
+f15afa7141fa7ab0