diff --git a/core/autoload/fonts.el b/core/autoload/fonts.el
new file mode 100644
index 000000000..6b1272eaa
--- /dev/null
+++ b/core/autoload/fonts.el
@@ -0,0 +1,100 @@
+;;; core/autoload/fonts.el -*- lexical-binding: t; -*-
+
+(defvar doom-font-increment 2
+  "How many steps to increase the font size each time `doom/increase-font-size'
+or `doom/decrease-font-size' are invoked.")
+
+(defvar doom-big-font-increment 14
+  "How many steps to increase the font size (with `doom-font' as the base) when
+`doom-big-font-mode' is enabled.")
+
+(defvar doom-change-font-size-hook nil
+  "A hook run after adjusting the font size with `doom/increase-font-size',
+`doom/decrease-font-size', or `doom/reset-font-size'.")
+
+
+;;
+;;; Library
+
+(defun doom--font-name (fontname frame)
+  (when (query-fontset fontname)
+    (when-let* ((ascii (assq 'ascii (aref (fontset-info fontname frame) 2))))
+      (setq fontname (nth 2 ascii))))
+  (or (x-decompose-font-name fontname)
+      (error "Cannot decompose font name")))
+
+;;;###autoload
+(defun doom-adjust-font-size (increment &optional frame)
+  "Increase size of font in FRAME by INCREMENT.
+Interactively, INCREMENT is given by the prefix argument.
+Optional FRAME parameter defaults to current frame."
+  (interactive "p")
+  (let* ((frame (or frame (selected-frame)))
+         (font (frame-parameter frame 'font))
+         (font (doom--font-name font frame)))
+    (let ((new-size (+ (string-to-number (aref font xlfd-regexp-pixelsize-subnum))
+                       increment)))
+      (unless (> new-size 0)
+        (error "Font is to small at %d" new-size))
+      (aset font xlfd-regexp-pixelsize-subnum (number-to-string new-size)))
+    ;; Set point size & width to "*", so frame width will adjust to new font size
+    (aset font xlfd-regexp-pointsize-subnum "*")
+    (aset font xlfd-regexp-avgwidth-subnum "*")
+    (setq font (x-compose-font-name font))
+    (unless (x-list-fonts font)
+      (error "Cannot change font size"))
+    (modify-frame-parameters frame `((font . ,font)))))
+
+
+;;
+;;; Commands
+
+;;;###autoload
+(defun doom/increase-font-size (count)
+  "Enlargens the font size across the current frame."
+  (interactive "p")
+  (let ((zoom-factor (or (frame-parameter nil 'font-scale) 0))
+        (increment (* count doom-font-increment)))
+    (setq zoom-factor (+ zoom-factor increment))
+    (if (= zoom-factor 0)
+        (doom/reset-font-size)
+      (doom-adjust-font-size increment)
+      (modify-frame-parameters nil `((font-scale . ,zoom-factor)))
+      (run-hooks 'doom-change-font-size-hook))))
+
+;;;###autoload
+(defun doom/decrease-font-size (count)
+  "Shrinks the font size across the current frame."
+  (interactive "p")
+  (doom/increase-font-size (- count)))
+
+;;;###autoload
+(defun doom/reset-font-size ()
+  "Reset font size.
+
+Assuming it has been adjusted via `doom/increase-font-size' and
+`doom/decrease-font-size'."
+  (interactive)
+  (let ((zoom-factor (frame-parameter nil 'font-scale)))
+    (if (not zoom-factor)
+        (user-error "Font size hasn't been changed")
+      (set-frame-font doom-font t)
+      (modify-frame-parameters nil '((font-scale)))
+      (run-hooks 'doom-change-font-size-hook))))
+
+;;;###autoload
+(define-minor-mode doom-big-font-mode
+  "A global mode that resizes the font, for streams, screen-sharing and
+presentations.
+
+This uses `doom/increase-font-size' under the hood, and enlargens the font by
+`doom-big-font-increment'."
+  :init-value nil
+  :lighter " BIG"
+  :global t
+  (unless doom-font
+    (user-error "`doom-font' must be set to a valid font"))
+  (let ((frame (selected-frame)))
+    (set-frame-font doom-font t (list frame))
+    (when doom-big-font-mode
+      (doom-adjust-font-size doom-big-font-increment frame))))
diff --git a/core/autoload/hydras.el b/core/autoload/hydras.el
index 407289148..68f6b4360 100644
--- a/core/autoload/hydras.el
+++ b/core/autoload/hydras.el
@@ -5,9 +5,9 @@
   "
       Text zoom: _j_:zoom in, _k_:zoom out, _0_:reset
 "
-  ("j" text-scale-increase "in")
-  ("k" text-scale-decrease "out")
-  ("0" (text-scale-set 0) "reset"))
+  ("j" doom/increase-font-size "in")
+  ("k" doom/decrease-font-size "out")
+  ("0" doom/reset-font-size "reset"))
 
 ;;;###autoload (autoload 'doom-window-nav-hydra/body "core/autoload/hydras" nil t)
 (defhydra doom-window-nav-hydra (:hint nil)
diff --git a/core/autoload/ui.el b/core/autoload/ui.el
index dad427c58..a631c7b6b 100644
--- a/core/autoload/ui.el
+++ b/core/autoload/ui.el
@@ -183,30 +183,3 @@ Inspired from http://demonastery.org/2013/04/emacs-evil-narrow-region/"
          (setq doom--buffer-narrowed-origin nil))
         (t
          (widen))))
-
-
-;;
-;; Modes
-
-;;;###autoload
-(define-minor-mode doom-big-font-mode
-  "A global mode that resizes the font, for streams, screen-sharing and
-presentations.
-
-Uses `doom-big-font' when enabled."
-  :init-value nil
-  :lighter " BIG"
-  :global t
-  (unless doom-big-font
-    (user-error "`doom-big-font' must be set to a valid font"))
-  (unless doom-font
-    (user-error "`doom-font' must be set to a valid font"))
-  (let ((doom-font (if doom-big-font-mode
-                       doom-big-font
-                     doom-font)))
-    (setf (alist-get 'font default-frame-alist)
-          (cond ((null doom-font))
-                ((stringp doom-font) doom-font)
-                ((fontp doom-font) (font-xlfd-name doom-font))
-                ((signal 'wrong-type-argument (list '(fontp stringp) doom-font)))))
-    (set-frame-font doom-font t t)))
diff --git a/core/core-ui.el b/core/core-ui.el
index 1b3dfb25c..818b8487a 100644
--- a/core/core-ui.el
+++ b/core/core-ui.el
@@ -20,10 +20,6 @@ Examples:
   (setq doom-font (font-spec :family \"Fira Mono\" :size 12))
   (setq doom-font \"Terminus (TTF):pixelsize=12:antialias=off\")")
 
-(defvar doom-big-font nil
-  "The font to use when `doom-big-font-mode' is enabled. Expects either a
-`font-spec' or a XFT font string. See `doom-font' for examples.")
-
 (defvar doom-variable-pitch-font nil
   "The font to use for variable-pitch text.
 
diff --git a/modules/config/default/+emacs-bindings.el b/modules/config/default/+emacs-bindings.el
index 21d65879c..7f133b4c9 100644
--- a/modules/config/default/+emacs-bindings.el
+++ b/modules/config/default/+emacs-bindings.el
@@ -22,9 +22,9 @@
       "<C-mouse-4>"      #'text-scale-increase
       "<C-mouse-5>"      #'text-scale-decrease
       "<C-down-mouse-2>" (λ! (text-scale-set 0))
-      "M-+" (λ! (text-scale-set 0))
-      "M-=" #'text-scale-increase
-      "M--" #'text-scale-decrease
+      "M-+" #'doom/reset-font-size
+      "M-=" #'doom/increase-font-size
+      "M--" #'doom/decrease-font-size
       ;; Editor related bindings
       [remap newline]  #'newline-and-indent
       "C-j"            #'+default/newline
diff --git a/modules/config/default/config.el b/modules/config/default/config.el
index 4cc12af84..524823b29 100644
--- a/modules/config/default/config.el
+++ b/modules/config/default/config.el
@@ -162,9 +162,9 @@
         "s-v" #'yank
         "s-s" #'save-buffer
         ;; Buffer-local font scaling
-        "s-+" (λ! (text-scale-set 0))
-        "s-=" #'text-scale-increase
-        "s--" #'text-scale-decrease
+        "s-+" #'doom/reset-font-size
+        "s-=" #'doom/increase-font-size
+        "s--" #'doom/decrease-font-size
         ;; Conventional text-editing keys & motions
         "s-a" #'mark-whole-buffer
         :g "s-/" (λ! (save-excursion (comment-line 1)))
diff --git a/modules/ui/modeline/autoload.el b/modules/ui/modeline/autoload.el
index 3c7478a65..dbc37836a 100644
--- a/modules/ui/modeline/autoload.el
+++ b/modules/ui/modeline/autoload.el
@@ -11,18 +11,22 @@
 
 
 (defvar +modeline--old-bar-height nil)
-;;;###autoload
-(defun +modeline|resize-for-big-font ()
-  "Adjust the modeline's height when `doom-big-font-mode' is enabled. This was
-made to be added to `doom-big-font-mode-hook'."
+(defun +modeline|resize-for-font ()
+  "Adjust the modeline's height when the font size is changed by
+`doom/increase-font-size' or `doom/decrease-font-size'.
+
+Meant for `doom-change-font-size-hook'."
   (unless +modeline--old-bar-height
     (setq +modeline--old-bar-height doom-modeline-height))
-  (let ((default-height +modeline--old-bar-height))
-    (if doom-big-font-mode
-        (let* ((font-size (font-get doom-font :size))
-               (big-size (font-get doom-big-font :size))
-               (ratio (/ (float big-size) font-size)))
-          (setq doom-modeline-height (ceiling (* default-height ratio 0.75))))
+  (let ((default-height +modeline--old-bar-height)
+        (scale (or (frame-parameter nil 'font-scale) 0)))
+    (if (> scale 0)
+        (let* ((font-size (string-to-number
+                           (aref (doom--font-name (frame-parameter nil 'font)
+                                                  (selected-frame))
+                                 xlfd-regexp-pixelsize-subnum)))
+               (scale (frame-parameter nil 'font-scale)))
+          (setq doom-modeline-height (+ default-height (* scale doom-font-increment))))
       (setq doom-modeline-height default-height))
     ;; already has a variable watcher in Emacs 26+
     (unless EMACS26+ (doom-modeline-refresh-bars))))
diff --git a/modules/ui/modeline/config.el b/modules/ui/modeline/config.el
index 3153784d8..77e6638d2 100644
--- a/modules/ui/modeline/config.el
+++ b/modules/ui/modeline/config.el
@@ -34,7 +34,7 @@
   (add-hook 'doom-modeline-mode-hook #'size-indication-mode) ; filesize in modeline
   (add-hook 'doom-modeline-mode-hook #'column-number-mode)   ; cursor column in modeline
 
-  (add-hook 'doom-big-font-mode-hook #'+modeline|resize-for-big-font)
+  (add-hook 'doom-change-font-size-hook #'+modeline|resize-for-font)
   (add-hook 'doom-load-theme-hook #'doom-modeline-refresh-bars)
 
   (add-hook '+doom-dashboard-mode-hook #'doom-modeline-set-project-modeline)