DeepL is undoubtedly one of the most powerful machine translation engines available today, but its official API’s steep pricing and restrictive request limits often leave developers searching for alternatives. If you’re looking for a solution that combines power with affordability, DeepLX is your answer.

Originally pioneered by OwO-Network, DeepLX provides developers with a free alternative to the DeepL API. Our implementation takes this concept further—it’s a serverless version specifically optimized for Cloudflare Workers that’s not only completely free but also outperforms the official API and other implementations in speed, stability, and request handling capacity.

1. Breaking Down Barriers: Free Meets Performance

What makes DeepLX compelling is how it completely eliminates the commercial barriers of the official API.

Completely Free: No API keys, no subscription fees, no usage limits. Deploy once, use forever.

Superior Performance: Thanks to intelligent architecture and Cloudflare’s global edge network, DeepLX delivers impressive performance metrics:

Metric DeepL API DeepLX (Pre-deployed Instance)
Rate Limit 50 requests/sec 80 requests/sec (8 req/sec × 10 proxy endpoints)
Average Network RTT ~450ms ~180ms (edge network acceleration)
HTTP 429 Error Rate 10-30% <1%
Geographic Distribution Limited 330+ global edge nodes

2. Technical Architecture: Intelligent Design for High Availability

DeepLX’s exceptional performance stems from its carefully engineered architecture, designed for high concurrency, low latency, and maximum uptime.

graph TB
    subgraph "Client Layer"
        Client[API Client]
    end
    subgraph "Cloudflare Workers"
        direction TB
        Router[Hono Router]
        subgraph "API Endpoints"
            Translate[POST /translate]
        end
        subgraph "Core Components"
            Security[Security Middleware]
            RateLimit[Rate Limiting]
            Cache[Dual-Layer Cache]
            Query[Translation Engine]
            Proxy[Proxy Management]
        end
    end
    subgraph "Cloudflare Storage"
        CacheKV[(Cache KV)]
        RateLimitKV[(Rate Limit KV)]
    end
    subgraph "Translation Services"
        XDPL[XDPL Proxy Cluster]
    end
    Client --> Router
    Router --> Translate
    Translate --> Security --> RateLimit --> Cache --> Query --> Proxy
    Cache -.-> CacheKV
    RateLimit -.-> RateLimitKV
    Proxy --> XDPL

Intelligent Load Balancing: Manages a pool of proxy endpoints through rotation and health checks, intelligently distributing requests to available nodes. This breaks through single-point request limitations and dramatically increases concurrent processing capacity.

Edge Computing Advantage: Deployed on Cloudflare Workers, code runs across 330+ global edge nodes. User requests are automatically routed to the nearest node, significantly reducing network latency.

Circuit Breaker Pattern: When a proxy endpoint experiences consecutive failures, the circuit breaker automatically opens, temporarily removing it from the request pool before attempting recovery. This prevents cascading failures and maintains overall service availability.

Smart Retry with Exponential Backoff: For transient errors like network fluctuations, DeepLX doesn’t fail immediately. Instead, it uses exponential backoff for intelligent retries, significantly improving final request success rates.

Dual-Layer Caching: Combines memory cache with Cloudflare KV distributed cache. Memory cache provides millisecond-level ultra-fast access, while KV cache ensures data persistence and sharing across the edge network, effectively reducing repeated backend service pressure.

3. Security and Stability: Enterprise-Grade Protection

DeepLX was designed from the ground up with security and stability in mind, offering multi-dimensional protection strategies.

Comprehensive Input Validation: Strict type, format, and length validation for all incoming request parameters, preventing malicious input at the source.

Multi-Dimensional Rate Limiting: Rate limiting based not only on client IP but also independent rate control for each backend proxy endpoint, effectively preventing abuse and DDoS attacks.

Security Header Injection: Automatically adds HTTP security headers like X-XSS-Protection and Content-Security-Policy to all responses, enhancing client-side security.

4. Quick Start: Get Running Immediately

No complex configuration needed—you can start using DeepLX right away.

Online Service: Our official pre-deployed instance at https://dplx.xi-xu.me is ready for testing and integration.

Code Examples:

cURL:

curl -X POST https://dplx.xi-xu.me/translate \
    -H "Content-Type: application/json" \
    -d '{
    "text": "Hello, world!",
    "source_lang": "EN",
    "target_lang": "ZH"
    }'

JavaScript:

async function translate(text) {
    const response = await fetch('https://dplx.xi-xu.me/translate', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
        text: text,
        source_lang: 'auto',
        target_lang: 'ZH'
    })
    });
    const result = await response.json();
    return result.data;
}
translate('Hello, world!').then(console.log);

Python:

import requests

def translate(text):
    response = requests.post(
        'https://dplx.xi-xu.me/translate',
        json={'text': text, 'source_lang': 'auto', 'target_lang': 'ZH'}
    )
    return response.json()['data']

print(translate('Hello, world!'))

5. Ecosystem Integration: Seamless Tool Integration

DeepLX integrates seamlessly with popular translation tools to enhance your workflow.

  • Immersive Translate: Add DeepLX as a custom translation service in settings.
  • Pot (Windows/macOS/Linux): Change the DeepL service type to DeepLX in service settings and enter the custom URL.
  • Bob (macOS): Install the bob-plugin-deeplx plugin for easy configuration.

6. Open Source Spirit: Transparent, Reliable, Community-Driven

DeepLX isn’t just a tool—it’s an open and transparent open-source project. Our implementation builds on the core concepts of OwO-Network/DeepLX while providing comprehensive optimization for modern serverless architecture.

MIT License: Fully open source with the permissive MIT license, allowing free use and modification with commercial-friendly terms.

Comprehensive Test Suite: The repository features over 565 automated test cases covering unit, integration, and performance testing dimensions, ensuring code quality and reliability.

Clear Documentation: Provides detailed documentation in both Chinese and English, including architecture analysis, deployment guides, and API references to help developers get started quickly.

Honoring Origins: Thanks to the OwO-Network team’s pioneering work that laid the foundation for the entire DeepLX ecosystem.

Conclusion

Our DeepLX implementation has become the perfect alternative to the DeepL API through its free, high-performance, and highly available characteristics. As a modern evolution of the OwO-Network/DeepLX concept, we focus on serverless architecture optimization to deliver superior performance for users.

Whether you’re an individual developer, small team, or user handling large-scale translation tasks, our DeepLX implementation provides a stable, efficient, and zero-cost solution.

Visit our DeepLX GitHub repository to start experiencing it today. If you find this repository helpful, please give it a ⭐ star! We also encourage you to follow OwO-Network/DeepLX to learn about the complete DeepLX ecosystem.