diff --git a/common/bech32.c b/common/bech32.c
index 7e949f6c3..ccf79d5b1 100644
--- a/common/bech32.c
+++ b/common/bech32.c
@@ -55,7 +55,7 @@ const int8_t bech32_charset_rev[128] = {
      1,  0,  3, 16, 11, 28, 12, 14,  6,  4,  2, -1, -1, -1, -1, -1
 };
 
-int bech32_encode(char *output, const char *hrp, const uint8_t *data, size_t data_len, size_t max_input_len, bech32_encoding enc) {
+int bech32_encode(char *output, const char *hrp, const uint8_t *data, size_t data_len, size_t max_output_len, bech32_encoding enc) {
     uint32_t chk = 1;
     size_t i = 0;
     while (hrp[i] != 0) {
@@ -68,7 +68,7 @@ int bech32_encode(char *output, const char *hrp, const uint8_t *data, size_t dat
         chk = bech32_polymod_step(chk) ^ (ch >> 5);
         ++i;
     }
-    if (i + 7 + data_len > max_input_len) return 0;
+    if (i + 7 + data_len > max_output_len) return 0;
     chk = bech32_polymod_step(chk);
     while (*hrp != 0) {
         chk = bech32_polymod_step(chk) ^ (*hrp & 0x1f);
diff --git a/common/bech32.h b/common/bech32.h
index 614ad321e..794510be2 100644
--- a/common/bech32.h
+++ b/common/bech32.h
@@ -83,7 +83,7 @@ typedef enum {
  *  In: hrp :     Pointer to the null-terminated human readable part.
  *      data :    Pointer to an array of 5-bit values.
  *      data_len: Length of the data array.
- *      max_input_len: Maximum valid length of input (90 for segwit usage).
+ *      max_output_len: Maximum valid length of output (90 for segwit usage).
  *      enc:      Which encoding to use (BECH32_ENCODING_BECH32{,M}).
  *  Returns 1 if successful.
  */
@@ -92,7 +92,7 @@ int bech32_encode(
     const char *hrp,
     const uint8_t *data,
     size_t data_len,
-    size_t max_input_len,
+    size_t max_output_len,
     bech32_encoding enc
 );