diff --git a/.gitignore b/.gitignore
index 3a72982..2a1f7d1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,3 +11,6 @@ venv/
 # (p. ej. ejemplos o tests).
 /*.gif
 /*.fnt
+
+# Estado persistente de la GUI (último TTF/tamaño)
+/.font_gen_gui_state.json
diff --git a/font_gen_gui.py b/font_gen_gui.py
index c159393..e991a5c 100644
--- a/font_gen_gui.py
+++ b/font_gen_gui.py
@@ -8,6 +8,7 @@ a este script al pulsar GENERAR.
 
 from __future__ import annotations
 
+import json
 import os
 import tkinter as tk
 from tkinter import filedialog, messagebox, ttk
@@ -18,6 +19,7 @@ import font_gen
 
 
 SCRIPT_DIR          = os.path.dirname(os.path.abspath(__file__))
+STATE_FILE          = os.path.join(SCRIPT_DIR, ".font_gen_gui_state.json")
 PREVIEW_MAX_W       = 720
 PREVIEW_MAX_H       = 320
 PREVIEW_DEBOUNCE_MS = 200
@@ -48,10 +50,17 @@ class FontGenApp(tk.Tk):
         self._adv_visible = False
 
         self._build_ui()
+        self._load_state()  # antes de los traces: el set() inicial no debe disparar preview
 
         for v in (self.ttf_var, self.size_var, self.columns_var, self.bw_var, self.bh_var):
             v.trace_add("write", lambda *_: self._schedule_preview())
 
+        # Disparar un preview inicial si _load_state nos dejó un TTF válido.
+        if self.ttf_var.get().strip():
+            self._schedule_preview()
+
+        self.protocol("WM_DELETE_WINDOW", self._on_close)
+
     # ------------------------------------------------------------------ UI
     def _build_ui(self) -> None:
         root = ttk.Frame(self, padding=8)
@@ -285,6 +294,38 @@ class FontGenApp(tk.Tk):
             f"✓ {os.path.basename(gif_path)} y {os.path.basename(fnt_path)} guardados"
         )
 
+    # ---------------------------------------------------------- Persistencia
+    def _load_state(self) -> None:
+        try:
+            with open(STATE_FILE, "r", encoding="utf-8") as f:
+                state = json.load(f)
+        except (FileNotFoundError, ValueError, OSError):
+            return
+        ttf = state.get("ttf", "")
+        if isinstance(ttf, str) and ttf and os.path.isfile(ttf):
+            self.ttf_var.set(ttf)
+            if not self.output_var.get().strip():
+                self.output_var.set(os.path.splitext(os.path.basename(ttf))[0])
+        size = state.get("size")
+        if isinstance(size, int) and 4 <= size <= 256:
+            self.size_var.set(size)
+
+    def _save_state(self) -> None:
+        try:
+            size = self.size_var.get()
+        except tk.TclError:
+            size = 8
+        state = {"ttf": self.ttf_var.get().strip(), "size": size}
+        try:
+            with open(STATE_FILE, "w", encoding="utf-8") as f:
+                json.dump(state, f, indent=2)
+        except OSError:
+            pass  # nice-to-have, no crítico si no se puede escribir.
+
+    def _on_close(self) -> None:
+        self._save_state()
+        self.destroy()
+
 
 def _parse_optional_positive_int(s: str) -> int | None:
     s = s.strip()