diff --git a/NEWS.md b/NEWS.md
index 199ee89bf..ea5ec49fa 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -21,6 +21,8 @@ rearrangements of Notcurses.
     its third argument. This is the absolute time viz `CLOCK_MONOTONIC` through
     which the frame ought be displayed. The callback must now effect delay.
   * Mouse coordinates are now properly translated for any margins.
+  * `qprefix()` and `bprefix()` now take a `uintmax_t` in place of an
+    `unsigned`, to match `ncprefix`.
 
 * 1.4.1 (2020-05-11)
   * No user-visible changes (fixed two unit tests).
diff --git a/include/ncpp/NotCurses.hh b/include/ncpp/NotCurses.hh
index f5eb9a26c..99e3566a2 100644
--- a/include/ncpp/NotCurses.hh
+++ b/include/ncpp/NotCurses.hh
@@ -61,17 +61,17 @@ namespace ncpp
 			return *_instance == nullptr || _instance->nc == nullptr;
 		}
 
-		static const char* ncmetric (uintmax_t val, unsigned decimal, char *buf, int omitdec, unsigned mult, int uprefix) noexcept
+		static const char* ncmetric (uintmax_t val, uintmax_t decimal, char *buf, int omitdec, unsigned mult, int uprefix) noexcept
 		{
 			return ::ncmetric (val, decimal, buf, omitdec, mult, uprefix);
 		}
 
-		static const char* qprefix (uintmax_t val, unsigned decimal, char *buf, int omitdec) noexcept
+		static const char* qprefix (uintmax_t val, uintmax_t decimal, char *buf, int omitdec) noexcept
 		{
 			return ::qprefix (val, decimal, buf, omitdec);
 		}
 
-		static const char* bprefix (uintmax_t val, unsigned decimal, char *buf, int omitdec) noexcept
+		static const char* bprefix (uintmax_t val, uintmax_t decimal, char *buf, int omitdec) noexcept
 		{
 			return ::bprefix (val, decimal, buf, omitdec);
 		}
diff --git a/include/notcurses/notcurses.h b/include/notcurses/notcurses.h
index a40487680..ab9465963 100644
--- a/include/notcurses/notcurses.h
+++ b/include/notcurses/notcurses.h
@@ -2387,13 +2387,13 @@ API const char* ncmetric(uintmax_t val, uintmax_t decimal, char* buf,
 
 // Mega, kilo, gigafoo. Use PREFIXSTRLEN + 1.
 static inline const char*
-qprefix(uintmax_t val, unsigned decimal, char* buf, int omitdec){
+qprefix(uintmax_t val, uintmax_t decimal, char* buf, int omitdec){
   return ncmetric(val, decimal, buf, omitdec, 1000, '\0');
 }
 
 // Mibi, kebi, gibibytes. Use BPREFIXSTRLEN + 1.
 static inline const char*
-bprefix(uintmax_t val, unsigned decimal, char* buf, int omitdec){
+bprefix(uintmax_t val, uintmax_t decimal, char* buf, int omitdec){
   return ncmetric(val, decimal, buf, omitdec, 1024, 'i');
 }
 
diff --git a/src/lib/metric.c b/src/lib/metric.c
index b301ac597..41848f13f 100644
--- a/src/lib/metric.c
+++ b/src/lib/metric.c
@@ -5,8 +5,7 @@
 #include "notcurses/notcurses.h"
 
 const char *ncmetric(uintmax_t val, uintmax_t decimal, char *buf, int omitdec,
-                     unsigned mul, int uprefix){
-  const unsigned mult = mul; // FIXME kill
+                     unsigned mult, int uprefix){
   // these two must have the same number of elements
   const wchar_t prefixes[] =    L"KMGTPEZY"; // 10^21-1 encompasses 2^64-1
   const wchar_t subprefixes[] = L"mµnpfazy"; // 10^24-1