diff --git a/src/app.js b/src/app.js
index f0106da..01cb97c 100644
--- a/src/app.js
+++ b/src/app.js
@@ -2,6 +2,7 @@ import { $ } from "./dom.js";
 import { initEvents, updateOptionVisibility } from "./events.js";
 import { applyLanguage, getSavedLang, loadI18n } from "./i18n.js";
 import { loadHistory, loadMode, loadSession, state } from "./state.js";
+import { parseUrlParams, applyUrlParamsToUI, applyUrlConfigToUI } from "./url-params.js";
 
 async function initializeApp() {
   await loadI18n();
@@ -10,15 +11,24 @@ async function initializeApp() {
   loadHistory();
   loadMode();
 
-  const session = loadSession();
-  $("input-text").value = session.input;
-  $("output-text").value = session.output;
+  const urlParams = parseUrlParams();
 
   await new Promise(r => setTimeout(r, 100));
 
   applyLanguage();
   initEvents();
   updateOptionVisibility();
+
+  if (urlParams.text) {
+    await applyUrlParamsToUI(urlParams);
+  } else {
+    applyUrlConfigToUI(urlParams);
+    const session = loadSession();
+    if (session.input) {
+      $("input-text").value = session.input;
+      $("output-text").value = session.output;
+    }
+  }
   
   const topbar = $("app-title")?.closest(".topbar");
   if (topbar) {
diff --git a/src/events.js b/src/events.js
index de1207d..20109dd 100644
--- a/src/events.js
+++ b/src/events.js
@@ -2,6 +2,7 @@ import { $, escapeHtml, hideModal, showModal, showToast } from "./dom.js";
 import { setLang, t } from "./i18n.js";
 import { processText } from "./processor.js";
 import { clearHistoryStorage, loadCharLib, saveHistory, saveMode, saveSession, state } from "./state.js";
+import { syncUrlParams } from "./url-params.js";
 
 function renderLibraryModal() {
   loadCharLib().then(lib => {
@@ -40,6 +41,7 @@ export function initEvents() {
         saveMode(radio.value);
       }
     });
+    syncUrlParams();
   };
   for (const radio of modeRadios) radio.addEventListener('change', updateMode);
   modeRadios.forEach(radio => {
@@ -78,15 +80,34 @@ export function initEvents() {
   upper?.addEventListener('change', () => {
     if (upper.selected) lower.selected = false;
     updateOptionVisibility();
+    syncUrlParams();
   });
   lower?.addEventListener('change', () => {
     if (lower.selected) upper.selected = false;
     updateOptionVisibility();
+    syncUrlParams();
   });
 
-  $("suffix-select")?.addEventListener("change", updateOptionVisibility);
-  $("dbvowel")?.addEventListener("change", updateOptionVisibility);
-  $("addHash")?.addEventListener("change", updateOptionVisibility);
+  $("suffix-select")?.addEventListener("change", () => {
+    updateOptionVisibility();
+    syncUrlParams();
+  });
+  $("dbvowel")?.addEventListener("change", () => {
+    updateOptionVisibility();
+    syncUrlParams();
+  });
+  $("addHash")?.addEventListener("change", () => {
+    updateOptionVisibility();
+    syncUrlParams();
+  });
+
+  // Sync URL when any More Settings input changes
+  ["custom-prefix", "custom-suffix", "custom-repeat", "custom-repeat-count",
+   "dbvowel-count", "hash-length", "numcir", "preserveEsc"].forEach(id => {
+    const el = $(id);
+    const eventType = el?.tagName === "MD-SWITCH" ? "change" : "input";
+    el?.addEventListener(eventType, syncUrlParams);
+  });
 
   $("process-btn")?.addEventListener("click", async () => {
     const text = $("input-text")?.value || "";
@@ -110,6 +131,7 @@ export function initEvents() {
       const result = await processText(text, options);
       $("output-text").value = result;
       saveSession(text, result);
+      syncUrlParams();
       if (text.trim()) {
         state.processingHistory.unshift({
           timestamp: Date.now(),
@@ -126,8 +148,11 @@ export function initEvents() {
   $("clear-btn")?.addEventListener("click", () => {
     $("input-text").value = "";
     $("output-text").value = "";
+    syncUrlParams();
   });
 
+  $("input-text")?.addEventListener("input", syncUrlParams);
+
   $("copy-btn")?.addEventListener("click", async () => {
     const val = $("output-text")?.value;
     if (val) {
diff --git a/src/url-params.js b/src/url-params.js
new file mode 100644
index 0000000..5e366f2
--- /dev/null
+++ b/src/url-params.js
@@ -0,0 +1,200 @@
+import { $ } from "./dom.js";
+import { updateOptionVisibility } from "./events.js";
+import { processText } from "./processor.js";
+import { saveSession, saveHistory, state } from "./state.js";
+
+const DEFAULTS = {
+  mode: "XA",
+  suffix: "0",
+  customPrefix: "[",
+  customSuffix: "]",
+  customRepeatCount: 7,
+  dbvowelCount: 1,
+  hashLength: 5,
+  upper: false,
+  lower: false,
+  dbvowel: false,
+  numcir: false,
+  addHash: false,
+  preserveEsc: false,
+};
+
+function parseBool(value) {
+  return value?.toLowerCase() === "true";
+}
+
+function parseNumber(value, fallback) {
+  const num = Number(value);
+  return Number.isFinite(num) ? num : fallback;
+}
+
+export function parseUrlParams() {
+  const params = new URLSearchParams(window.location.search);
+
+  const letterRaw = params.get("letter");
+  const letter = ["upper", "lower"].includes(letterRaw) ? letterRaw : "normal";
+
+  return {
+    text: params.get("text") || undefined,
+    mode: params.get("mode") || DEFAULTS.mode,
+    upper: letter === "upper",
+    lower: letter === "lower",
+    suffix: params.get("suffix") || DEFAULTS.suffix,
+    customPrefix: params.get("customPrefix") ?? DEFAULTS.customPrefix,
+    customSuffix: params.get("customSuffix") ?? DEFAULTS.customSuffix,
+    customRepeat: params.get("customRepeat") || undefined,
+    customRepeatCount: parseNumber(params.get("customRepeatCount"), DEFAULTS.customRepeatCount),
+    dbvowel: parseBool(params.get("dbvowel")),
+    dbvowelCount: parseNumber(params.get("dbvowelCount"), DEFAULTS.dbvowelCount),
+    numcir: parseBool(params.get("numcir")),
+    addHash: parseBool(params.get("addHash")),
+    hashLength: parseNumber(params.get("hashLength"), DEFAULTS.hashLength),
+    preserveEsc: parseBool(params.get("preserveEsc")),
+  };
+}
+
+export function applyUrlConfigToUI(params) {
+  const modeRadio = $(params.mode === "XB" ? "mode-xb" : "mode-xa");
+  if (modeRadio) {
+    modeRadio.checked = true;
+  }
+
+  const switches = ["upper", "lower", "dbvowel", "numcir", "addHash", "preserveEsc"];
+  for (const id of switches) {
+    const el = $(id);
+    if (el) {
+      el.selected = params[id] ?? DEFAULTS[id];
+    }
+  }
+
+  if ($("suffix-select")) {
+    $("suffix-select").value = params.suffix;
+  }
+
+  const textFields = {
+    "custom-prefix": params.customPrefix,
+    "custom-suffix": params.customSuffix,
+    "custom-repeat": params.customRepeat ?? "",
+    "custom-repeat-count": String(params.customRepeatCount),
+    "dbvowel-count": String(params.dbvowelCount),
+    "hash-length": String(params.hashLength),
+  };
+
+  for (const [id, value] of Object.entries(textFields)) {
+    const el = $(id);
+    if (el && value !== undefined) {
+      el.value = value;
+    }
+  }
+
+  updateOptionVisibility();
+}
+
+export async function applyUrlParamsToUI(params) {
+  applyUrlConfigToUI(params);
+
+  if (!params.text) return;
+
+  $("input-text").value = params.text;
+
+  const options = {
+    mode: params.mode,
+    upper: params.upper,
+    lower: params.lower,
+    suffix: params.suffix,
+    customPrefix: params.customPrefix,
+    customSuffix: params.customSuffix,
+    customRepeat: params.customRepeat || "",
+    customRepeatCount: params.customRepeatCount,
+    dbvowel: params.dbvowel,
+    dbvowelCount: params.dbvowelCount,
+    numcir: params.numcir,
+    addHash: params.addHash,
+    hashLength: params.hashLength,
+    preserveEsc: params.preserveEsc,
+  };
+
+  try {
+    const result = await processText(params.text, options);
+    $("output-text").value = result;
+    saveSession(params.text, result);
+    state.processingHistory.unshift({
+      timestamp: Date.now(),
+      input: params.text,
+      output: result
+    });
+    saveHistory(state.processingHistory);
+  } catch (e) {
+    $("output-text").value = `Error: ${e.message}`;
+  }
+}
+
+export function syncUrlParams() {
+  const params = new URLSearchParams();
+
+  const text = $("input-text")?.value || "";
+  if (text) params.set("text", text);
+
+  const mode = document.querySelector('md-radio[name="mode"]:checked')?.value || DEFAULTS.mode;
+  if (mode !== DEFAULTS.mode) {
+    params.set("mode", mode);
+  }
+
+  const upper = $("upper")?.selected ?? false;
+  const lower = $("lower")?.selected ?? false;
+  const letter = upper ? "upper" : lower ? "lower" : "normal";
+  if (letter !== "normal") params.set("letter", letter);
+
+  const suffix = $("suffix-select")?.value || DEFAULTS.suffix;
+  if (suffix !== DEFAULTS.suffix) {
+    params.set("suffix", suffix);
+  }
+
+  const customPrefix = $("custom-prefix")?.value ?? "";
+  if (customPrefix !== DEFAULTS.customPrefix) {
+    params.set("customPrefix", customPrefix);
+  }
+
+  const customSuffix = $("custom-suffix")?.value ?? "";
+  if (customSuffix !== DEFAULTS.customSuffix) {
+    params.set("customSuffix", customSuffix);
+  }
+
+  const customRepeat = $("custom-repeat")?.value || "";
+  if (customRepeat) {
+    params.set("customRepeat", customRepeat);
+  }
+
+  const customRepeatCount = parseInt($("custom-repeat-count")?.value, 10) || DEFAULTS.customRepeatCount;
+  if (customRepeatCount !== DEFAULTS.customRepeatCount) {
+    params.set("customRepeatCount", String(customRepeatCount));
+  }
+
+  const dbvowel = $("dbvowel")?.selected ?? false;
+  if (dbvowel) params.set("dbvowel", "true");
+
+  const dbvowelCount = parseInt($("dbvowel-count")?.value, 10) || DEFAULTS.dbvowelCount;
+  if (dbvowelCount !== DEFAULTS.dbvowelCount) {
+    params.set("dbvowelCount", String(dbvowelCount));
+  }
+
+  const numcir = $("numcir")?.selected ?? false;
+  if (numcir) params.set("numcir", "true");
+
+  const addHash = $("addHash")?.selected ?? false;
+  if (addHash) params.set("addHash", "true");
+
+  const hashLength = parseInt($("hash-length")?.value, 10) || DEFAULTS.hashLength;
+  if (hashLength !== DEFAULTS.hashLength) {
+    params.set("hashLength", String(hashLength));
+  }
+
+  const preserveEsc = $("preserveEsc")?.selected ?? false;
+  if (preserveEsc) params.set("preserveEsc", "true");
+
+  const url = params.toString()
+    ? `${window.location.pathname}?${params.toString()}`
+    : window.location.pathname;
+
+  history.replaceState(null, "", url);
+}