Youdao Translate API Developer Guide

The Youdao Translate API (Youdao AI Cloud Translation Service) is NetEase Youdao's machine translation interface service for developers, supporting text translation, speech translation, image translation, and document translation. Whether you're an independent developer, startup team, or enterprise client, you can integrate Youdao's translation capabilities into your applications, websites, or workflows through simple HTTP API calls. This guide walks you through the entire process from registration to your first successful API call.

The Youdao Translate API provides HTTP endpoints for machine translation workflows. Supported languages, free quota, pricing, and model details can change, so developers should verify the current API documentation before implementation.

Registration & API Key Setup

Before using the Youdao Translate API, you need to register on the Youdao AI Cloud platform and create an application to obtain your API credentials:

Making API Calls

Request Parameters

The core text translation endpoint is https://openapi.youdao.com/api. The key request parameters are:

• q — Text content to translate (UTF-8 encoded)
• from — Source language code (e.g., zh-CHS for Simplified Chinese, en for English, auto for auto-detection)
• to — Target language code
• appKey — Your Application ID
• salt — A random string (UUID works well)
• sign — Request signature (SHA-256 hash of appKey + input + salt + curtime + appSecret)
• signType — Signature type, always v3
• curtime — Current UTC timestamp in seconds

Python Example

Here's a complete Python example for calling the Youdao Translate API:

import hashlib
import uuid
import time
import requests

YOUDAO_URL = 'https://openapi.youdao.com/api'
APP_KEY = 'your_app_key'
APP_SECRET = 'your_app_secret'

def translate(text, from_lang='auto', to_lang='ja'):
    salt = str(uuid.uuid4())
    curtime = str(int(time.time()))
    sign_str = APP_KEY + truncate(text) + salt + curtime + APP_SECRET
    sign = hashlib.sha256(sign_str.encode('utf-8')).hexdigest()

    params = {
        'q': text,
        'from': from_lang,
        'to': to_lang,
        'appKey': APP_KEY,
        'salt': salt,
        'sign': sign,
        'signType': 'v3',
        'curtime': curtime,
    }
    response = requests.post(YOUDAO_URL, data=params)
    return response.json()

def truncate(text):
    if len(text) <= 20:
        return text
    return text[:10] + str(len(text)) + text[-10:]

result = translate('Hello, how are you?', 'en', 'zh-CHS')
print(result['translation'])

Node.js Example

const crypto = require('crypto');
const axios = require('axios');
const { v4: uuidv4 } = require('uuid');

const APP_KEY = 'your_app_key';
const APP_SECRET = 'your_app_secret';
const API_URL = 'https://openapi.youdao.com/api';

function truncate(q) {
  if (q.length <= 20) return q;
  return q.substring(0, 10) + q.length + q.substring(q.length - 10);
}

async function translate(text, from = 'auto', to = 'zh-CHS') {
  const salt = uuidv4();
  const curtime = Math.round(Date.now() / 1000).toString();
  const signStr = APP_KEY + truncate(text) + salt + curtime + APP_SECRET;
  const sign = crypto.createHash('sha256').update(signStr).digest('hex');

  const { data } = await axios.post(API_URL, null, {
    params: { q: text, from, to, appKey: APP_KEY, salt, sign, signType: 'v3', curtime }
  });
  return data;
}

translate('Hello World').then(res => console.log(res.translation));

Pricing & Plans

The Youdao Translate API offers both pay-as-you-go and prepaid pricing:

• Free Tier: 1 million characters per month at no cost — perfect for individual developers and small projects
• Pay-as-You-Go: Beyond the free tier, text translation costs approximately $6.50 per million characters
• Prepaid Packages: prepaid packages and unit prices vary; check the current API pricing page before estimating cost
• Enterprise Custom: Organizations translating over 50 million characters monthly can contact sales for custom pricing

Speech translation, image translation, and document translation have separate pricing models — refer to the official Youdao AI Cloud documentation for details. The API console provides detailed usage statistics and billing breakdowns, making it easy to monitor and manage your consumption.

Frequently Asked Questions