diff --git a/common/json_parse_simple.c b/common/json_parse_simple.c
index f7ce964ca..9fe94229c 100644
--- a/common/json_parse_simple.c
+++ b/common/json_parse_simple.c
@@ -88,6 +88,19 @@ bool json_to_u64(const char *buffer, const jsmntok_t *tok, u64 *num)
 	return true;
 }
 
+bool json_str_to_u64(const char *buffer, const jsmntok_t *tok, u64 *num)
+{
+	jsmntok_t temp;
+	if (tok->type != JSMN_STRING)
+		return false;
+
+	temp = *tok;
+	temp.start += 1;
+	temp.end -= 1;
+
+	return json_to_u64(buffer, &temp, num);
+}
+
 bool json_to_u32(const char *buffer, const jsmntok_t *tok, u32 *num)
 {
 	uint64_t u64;
diff --git a/common/json_parse_simple.h b/common/json_parse_simple.h
index 4188a4eb4..4092dad75 100644
--- a/common/json_parse_simple.h
+++ b/common/json_parse_simple.h
@@ -35,6 +35,10 @@ char *json_strdup(const tal_t *ctx, const char *buffer, const jsmntok_t *tok);
 /* Extract number from this (may be a string, or a number literal) */
 bool json_to_u64(const char *buffer, const jsmntok_t *tok, u64 *num);
 
+/* Extract number from string. The number must be the entirety of the
+ * string between the '"' */
+bool json_str_to_u64(const char *buffer, const jsmntok_t *tok, u64 *num);
+
 /* Extract number from this (may be a string, or a number literal) */
 bool json_to_u32(const char *buffer, const jsmntok_t *tok, u32 *num);