diff --git a/clash/clash.lisp b/clash/clash.lisp
index 3a68dbd..be1b84a 100644
--- a/clash/clash.lisp
+++ b/clash/clash.lisp
@@ -28,18 +28,20 @@
   "Metric power suffixes used in parse-byte-count.")
 (defparameter *byte-count-pattern*
   (cl-ppcre:create-scanner
-   (format nil "^\\s*(?(?=(?:^|[^0-9])\\.[0-9])|([0-9]+))\\.?((?<=\\.)[0-9]+)?~
-                \\s*(?:(?:([kmgtpezyrq])(i)?)?B)?$\\s*")
+   (format nil "^\\s*(?(?=\\.[0-9])\\.|([0-9]+))~
+                \\.?(?:(?<=\\.)(0*)([0-9]+))?~
+                \\s*(?:(?:([kmgtpezyrq])(i)?)?B)?$\\s*$")
    :extended-mode t
    :case-insensitive-mode t)
   "Regexp scanner for parse-byte-count.")
 
-(defun make-float (int dec)
+(defun make-float (int leading-zero-count dec)
   (if (zerop dec)
       (float int)
       (+ (float int)
          (* (if (minusp int) -1 1)
             (/ (float dec)
+               (expt 10 leading-zero-count)
                (expt 10 (1+ (floor (log dec 10)))))))))
 
 (defun find-suffix-expt (suffix)
@@ -51,10 +53,14 @@
 (defun parse-byte-count (string)
   "Parse a byte count from STRING."
   (or (ppcre:register-groups-bind
-          ((#'parse-integer int dec)
+          ((#'parse-integer int)
+           leading-zeros
+           (#'parse-integer dec)
            (#'find-suffix-expt power) base-two)
           (*byte-count-pattern* string :sharedp t)
-        (let ((count (* (make-float (or int 0) (or dec 0))
+        (let ((count (* (make-float (or int 0)
+                                    (length leading-zeros)
+                                    (or dec 0))
                         (expt (if base-two 1024 1000) (or power 0)))))
           (if (and (not power) (plusp (mod count 1)))
               (error "Byte count is not a natural number: ~A" count)