diff --git a/optipdf b/optipdf
index fc32636..13f6a33 100755
--- a/optipdf
+++ b/optipdf
@@ -116,43 +116,10 @@ file_size() {
 
 # produces a human-readable size from the byte count passed to it
 hr_size() (
-    declare -i BYTES=$1
-
-    #UNITS=(B KB MB GB TB PB EB ZB YB) # shell math can only go so far...
-    UNITS=(B KB MB GB TB)
-    FACT=1024
-    THRESH=9/10
-    DECIMALS=1
-    DECIMALS_FACTOR=$(( 10 ** DECIMALS ))
-
-    # cycle through units from largest to smallest, exiting when it finds the
-    # largest applicable unit
-    for (( EXP = ${#UNITS[@]} - 1; EXP > -1; --EXP )); do
-        # check if the unit is close enough to the unit's size, within the
-        # threshold
-        if [[ $BYTES -gt $((FACT ** EXP * $THRESH)) ]]; then
-            # we found the applicable unit
-
-            # must multiply by a factor of 10 here to not truncate
-            # the given number of decimal places after the point
-            HR_VAL=$(( BYTES * DECIMALS_FACTOR / FACT ** EXP ))
-
-            # put the decimal point in
-            if [[ $DECIMALS -gt 0 ]]; then
-                HR_VAL=$(( HR_VAL / DECIMALS_FACTOR )).$(( HR_VAL % DECIMALS_FACTOR ))
-            fi
-
-            HR_UNIT=${UNITS[$EXP]}
-            break
-        fi
-    done
-
-    if [[ -z $HR_UNIT ]]; then
-        HR_VAL=$BYTES
-        HR_UNIT=${UNITS[0]}
-    fi
-
-    printf '%g %s\n' "$HR_VAL" "$HR_UNIT"
+    numfmt \
+        --to=iec \
+        --suffix=B \
+        "$@"
 )
 
 setup_tempdir() {