(set-face-attribute 'default nil :height 100)

这个值的单位是1/10pt，所以100会给你10pt，以此类推。

我有以下在我的。emacs:

(defun fontify-frame (frame)
  (set-frame-parameter frame 'font "Monospace-11"))

;; Fontify current frame
(fontify-frame nil)
;; Fontify any future frames
(push 'fontify-frame after-make-frame-functions) 

你可以用你选择的任何字体来代替“Monospace-11”。可用选项集高度依赖于系统。使用M-x set-default-font并查看制表符补全会给您一些启发。在我的系统上，在启用了Emacs 23和抗锯齿的情况下，可以根据名称选择系统字体，例如Monospace、Sans Serif等。

Firefox和其他程序允许您使用C-+和C——来增加和减少字体大小。我设置了我的.emacs，这样我就可以通过添加以下几行代码来拥有同样的能力:

(global-set-key [C-kp-add] 'text-scale-increase)

(global-set-key [C-kp-subtract] 'text-scale-decrease)

在AquaMacs CMD +和CMD -中调整当前缓冲区的字体大小。

从Emacswiki, GNU Emacs 23有一个内置的键组合:

C-xC-+和C-xC-增加或 减小缓冲区文本大小

M-x自定义脸RET默认将允许您设置脸的默认脸，所有其他脸的基础上。在这里你可以设置字体大小。

这是我的。emacs中的内容。实际上，color-theme会设置基础，然后我的自定义面部设置会覆盖一些东西。定制的set-faces是由emacs的定制面机制编写的:

;; my colour theme is whateveryouwant :)
(require 'color-theme)
(color-theme-initialize)
(color-theme-whateveryouwant)

(custom-set-faces
  ;; custom-set-faces was added by Custom.
  ;; If you edit it by hand, you could mess it up, so be careful.
  ;; Your init file should contain only one such instance.
  ;; If there is more than one, they won't work right.
 '(default ((t (:stipple nil :background "white" :foreground "black" :inverse-video nil :box nil :strike-through nil :overline nil :underline nil :slant normal :weight normal :height 98 :width normal :foundry "unknown" :family "DejaVu Sans Mono"))))
 '(font-lock-comment-face ((t (:foreground "darkorange4"))))
 '(font-lock-function-name-face ((t (:foreground "navy"))))
 '(font-lock-keyword-face ((t (:foreground "red4"))))
 '(font-lock-type-face ((t (:foreground "black"))))
 '(linum ((t (:inherit shadow :background "gray95"))))
 '(mode-line ((t (nil nil nil nil :background "grey90" (:line-width -1 :color nil :style released-button) "black" :box nil :width condensed :foundry "unknown" :family "DejaVu Sans Mono")))))