diff --git a/jupyter-repl.el b/jupyter-repl.el
index 5c65f0f..5cc8d50 100644
--- a/jupyter-repl.el
+++ b/jupyter-repl.el
@@ -1550,12 +1550,13 @@ begiining of the symbol at point to look for a match of RE."
             (cons symbol t)
           symbol)))))
 
-(defun jupyter-completion-floating-point-p ()
-  "Return non-nil if the text before `point' may be a floating point number.
-If the preceeding two characters before point are \"[0-9].\"
-return non-nil, otherwise return nil."
-  (and (= (char-before (point)) ?.)
-       (<= ?0 (char-before (1- (point))) ?9)))
+(defun jupyter-completion-number-p ()
+  "Return non-nil if the text before `point' may be a floating point number."
+  (and (or (<= ?0 (char-before (point)) ?9)
+           (eq (char-before (point)) ?.))
+       (save-excursion
+         (skip-syntax-backward "w.")
+         (looking-at-p "[0-9]+\\.?[0-9]*"))))
 
 ;;; Extracting arguments from argument strings
 
diff --git a/jupyter-tests.el b/jupyter-tests.el
index 8413bb4..3c613a2 100644
--- a/jupyter-tests.el
+++ b/jupyter-tests.el
@@ -493,6 +493,24 @@ running BODY."
         (should (json-plist-p res))
         (should (eq (jupyter-message-type res) :shutdown-reply))))))
 
+(ert-deftest jupyter-completion ()
+  (ert-info ("`jupyter-completion-number-p'")
+    (with-temp-buffer
+      (insert "0.311")
+      (should (jupyter-completion-number-p))
+      (erase-buffer)
+      (insert "0311")
+      (should (jupyter-completion-number-p))
+      (erase-buffer)
+      (insert "0311.")
+      (should (jupyter-completion-number-p))
+      (erase-buffer)
+      (insert "100foo")
+      (should-not (jupyter-completion-number-p))
+      (erase-buffer)
+      (insert "foo100")
+      (should-not (jupyter-completion-number-p)))))
+
 (ert-deftest jupyter-repl ()
   (jupyter-with-python-repl client
     (should (jupyter-repl-client-has-manager-p))