diff --git a/showbits-thermal-printer-ui/src/components/CSegment.vue b/showbits-thermal-printer-ui/src/components/CSegment.vue
index 5509b49..6049245 100644
--- a/showbits-thermal-printer-ui/src/components/CSegment.vue
+++ b/showbits-thermal-printer-ui/src/components/CSegment.vue
@@ -1,18 +1,21 @@
 <script setup lang="ts">
 import { ref } from "vue";
+import CSegmentCalendar from "./CSegmentCalendar.vue";
 import CSegmentText from "./CSegmentText.vue";
 
-const mode = ref<"text">();
+const mode = ref<"calendar" | "text">();
 </script>
 
 <template>
   <div class="outer">
     <button v-if="mode" class="close" @click="mode = undefined">X</button>
+    <CSegmentCalendar v-if="mode === 'calendar'" />
     <CSegmentText v-if="mode === 'text'" />
-    <section v-else class="choose">
+    <hr v-if="mode !== undefined" />
+    <section>
       <p>What do you want to print?</p>
       <div class="list">
-        <button @click="mode = 'text'">Calendar</button>
+        <button @click="mode = 'calendar'">Calendar</button>
         <button @click="mode = 'text'">Cellular Automaton</button>
         <button @click="mode = 'text'">Chat Message</button>
         <button @click="mode = 'text'">Easter Egg</button>
@@ -55,6 +58,12 @@ const mode = ref<"text">();
   background-color: #666;
 }
 
+hr {
+  border: none;
+  border-top: 2px groove white;
+  margin: 32px -32px;
+}
+
 p {
   margin-bottom: 1ch;
 }
diff --git a/showbits-thermal-printer-ui/src/components/CSegmentCalendar.vue b/showbits-thermal-printer-ui/src/components/CSegmentCalendar.vue
new file mode 100644
index 0000000..4ce8bfc
--- /dev/null
+++ b/showbits-thermal-printer-ui/src/components/CSegmentCalendar.vue
@@ -0,0 +1,85 @@
+<script setup lang="ts">
+import { ref, useTemplateRef } from "vue";
+
+const form = useTemplateRef<HTMLFormElement>("form");
+const disabled = ref(false);
+const error = ref<string>();
+
+const today = new Date();
+const year = ref(today.getFullYear());
+const month = ref(today.getMonth() + 1);
+const feed = ref(true);
+
+async function waitAtLeast(duration: number, since: number): Promise<void> {
+  const now = Date.now();
+  const wait = duration - (now - since);
+  if (wait > 0) {
+    await new Promise((resolve) => setTimeout(resolve, wait));
+  }
+}
+
+async function submit(): Promise<void> {
+  const start = Date.now();
+  disabled.value = true;
+
+  try {
+    const data = new URLSearchParams();
+    data.append("year", String(year.value));
+    data.append("month", String(month.value));
+    data.append("feed", String(feed.value));
+    const response = await fetch("/api/calendar", {
+      method: "POST",
+      body: data,
+    });
+    if (!response.ok) {
+      const status = `${response.status.toFixed()} ${response.statusText}`;
+      const text = await response.text();
+      error.value = text.length > 0 ? `${status}: ${text}` : status;
+    }
+  } catch (err) {
+    error.value = String(err);
+  }
+
+  await waitAtLeast(500, start);
+  disabled.value = false;
+}
+</script>
+
+<template>
+  <form ref="form" @submit.prevent="submit">
+    <h2>Calendar</h2>
+    <label>Year: <input v-model="year" type="number" /></label>
+    <label>
+      Month:
+      <input v-model="month" type="number" min="1" max="12" />
+    </label>
+    <label><input v-model="feed" type="checkbox" :disabled /> Feed</label>
+    <button :disabled>Print</button>
+    <p v-if="error" class="error">{{ error }}</p>
+  </form>
+</template>
+
+<style scoped>
+form {
+  display: flex;
+  flex-direction: column;
+  gap: 16px;
+}
+
+input[type="number"] {
+  box-sizing: border-box;
+  width: 100%;
+}
+
+fieldset {
+  display: flex;
+  flex-direction: column;
+  border: none;
+}
+
+.error {
+  background-color: #fdd;
+  color: #400;
+  padding: 0 2px;
+}
+</style>