diff --git a/src/LlamaChatSession.ts b/src/LlamaChatSession.ts
index 382ca7c6..64ac7ed6 100644
--- a/src/LlamaChatSession.ts
+++ b/src/LlamaChatSession.ts
@@ -5,6 +5,7 @@ import {ChatPromptWrapper} from "./ChatPromptWrapper.js";
 import {LlamaChatPromptWrapper} from "./chatWrappers/LlamaChatPromptWrapper.js";
 import {AbortError} from "./AbortError.js";
 
+const UNKNOWN_UNICODE_CHAR = "�";
 
 export class LlamaChatSession {
     private readonly _model: LlamaModel;
@@ -65,46 +66,26 @@ export class LlamaChatSession {
     }
 
     private async _evalTokens(tokens: Uint32Array, onToken?: (tokens: number[]) => void, {signal}: { signal?: AbortSignal } = {}) {
+        const decodeTokens = (tokens: number[]) => this._model.decode(Uint32Array.from(tokens));
+
         const stopStrings = this._promptWrapper.getStopStrings();
         const stopStringIndexes = Array(stopStrings.length).fill(0);
         const skippedChunksQueue: number[] = [];
         const res: number[] = [];
 
-        let skipNextTokensEmoji = 0;
-        const decodeRes = () => this._model.decode(Uint32Array.from(res));
 
         for await (const chunk of this._model.evaluate(tokens)) {
             if (signal?.aborted)
                 throw new AbortError();
 
-            const tokenStr = this._model.decode(Uint32Array.from([chunk]));
-            let skipTokenEvent = false;
-
-            for (let stopStringIndex = 0; stopStringIndex < stopStrings.length; stopStringIndex++) {
-                const stopString = stopStrings[stopStringIndex];
-
-                let localShouldSkipTokenEvent = false;
-                for (let i = 0; i < tokenStr.length && stopStringIndexes[stopStringIndex] !== stopString.length; i++) {
-                    if (tokenStr[i] === stopString[stopStringIndexes[stopStringIndex]]) {
-                        stopStringIndexes[stopStringIndex]++;
-                        localShouldSkipTokenEvent = true;
-                    } else {
-                        stopStringIndexes[stopStringIndex] = 0;
-                        localShouldSkipTokenEvent = false;
-                        break;
-                    }
-                }
-
-                if (stopStringIndexes[stopStringIndex] === stopString.length) {
-                    return decodeRes();
-                }
-
-                skipTokenEvent ||= localShouldSkipTokenEvent;
-            }
+            const tokenStr = decodeTokens([chunk]);
+            const {shouldReturn, skipTokenEvent} = this._checkStopString(tokenStr, stopStringIndexes);
+            
+            if (shouldReturn)
+                return decodeTokens(res);
 
-            skipNextTokensEmoji += LlamaChatSession._calculateEmojiNextLength(chunk);
-            if (skipTokenEvent || skipNextTokensEmoji > 0) {
-                skipNextTokensEmoji--;
+            // if the token is unknown, it means it's not complete character
+            if (tokenStr === UNKNOWN_UNICODE_CHAR || skipTokenEvent) {
                 skippedChunksQueue.push(chunk);
                 continue;
             }
@@ -119,20 +100,35 @@ export class LlamaChatSession {
             onToken?.([chunk]);
         }
 
-        return decodeRes();
+        return decodeTokens(res);
     }
 
-    private static _calculateEmojiNextLength(firstByte: number) {
-        const byteText = firstByte.toString(2);
+    private _checkStopString(tokenStr: string, stopStringIndexes: number[]){
+        const stopStrings = this._promptWrapper.getStopStrings();
+        let skipTokenEvent = false;
+
+        for (let stopStringIndex = 0; stopStringIndex < stopStrings.length; stopStringIndex++) {
+            const stopString = stopStrings[stopStringIndex];
+
+            let localShouldSkipTokenEvent = false;
+            for (let i = 0; i < tokenStr.length && stopStringIndexes[stopStringIndex] !== stopString.length; i++) {
+                if (tokenStr[i] === stopString[stopStringIndexes[stopStringIndex]]) {
+                    stopStringIndexes[stopStringIndex]++;
+                    localShouldSkipTokenEvent = true;
+                } else {
+                    stopStringIndexes[stopStringIndex] = 0;
+                    localShouldSkipTokenEvent = false;
+                    break;
+                }
+            }
+
+            if (stopStringIndexes[stopStringIndex] === stopString.length) {
+                return {shouldReturn: true};
+            }
 
-        if (byteText.startsWith("11110")) {
-            return 3;
-        } else if (byteText.startsWith("1110")) {
-            return 2;
-        } else if (byteText.startsWith("110")) {
-            return 1;
+            skipTokenEvent ||= localShouldSkipTokenEvent;
         }
 
-        return 0;
+        return {skipTokenEvent};
     }
 }