DeepL¶

DeepL is a dedicated translation service known for high-quality translations, especially for European languages. TranslateBot supports DeepL as an alternative to LLM-based translation.

Why DeepL?¶

Free to try: new API accounts get a one-time credit of 1 million characters
Fast: Direct translation API, no prompt engineering overhead
Quality: Consistently high quality for supported language pairs
Simple: No model selection needed, just an API key

Setup¶

1. Install the DeepL extra¶

uvPoetrypip

uv add --dev translatebot-django[deepl]

poetry add --group dev translatebot-django[deepl]

pip install translatebot-django[deepl]

2. Get an API key¶

Sign up for a DeepL API account at deepl.com/pro-api. The Developer plan includes a one-time credit of 1 million characters. After that, the Growth plan includes 12 million characters per year, and extra characters are billed per million. See DeepL API plans for current prices.

3. Configure Django settings¶

settings.py

import os

TRANSLATEBOT_PROVIDER = "deepl"
TRANSLATEBOT_API_KEY = os.getenv("DEEPL_API_KEY")

That's it! Run the translate command as usual:

python manage.py translate --target-lang de

Supported Languages¶

DeepL supports 30+ target languages. TranslateBot automatically converts Django language codes to DeepL's format:

Django code	DeepL code	Language
`de`	`DE`	German
`fr`	`FR`	French
`nl`	`NL`	Dutch
`es`	`ES`	Spanish
`pt-br`	`PT-BR`	Portuguese (Brazil)
`en`	`EN-US`	English (US)
`zh-hans`	`ZH-HANS`	Chinese (Simplified)
`ja`	`JA`	Japanese

For the full list of supported languages, see the DeepL API documentation.

Regional defaults

When you use en or pt without a region suffix, TranslateBot defaults to EN-US and PT-BR respectively, as DeepL requires a regional variant for these languages.

Limitations¶

No TRANSLATING.md support¶

DeepL's API does not accept custom instructions like LLM providers do. If your project has a TRANSLATING.md file, TranslateBot will show a warning and ignore it when using DeepL:

📋 Found TRANSLATING.md but DeepL does not support custom context - ignoring

For custom terminology with DeepL, consider using DeepL glossaries directly.

Placeholder protection¶

TranslateBot automatically protects format placeholders (%(name)s, {placeholder}, %s, etc.) from being mangled by DeepL during translation. Placeholders are swapped for neutral tokens that DeepL leaves alone (such as ph0@tb.x) before sending, and restored in the result. HTML tags are preserved with DeepL's HTML tag handling.

Plural forms¶

DeepL can't translate into a language's specific plural forms. The singular and plural of each message are translated as two strings, and the plural translation is used for every form after the first. For languages with more than two plural forms (Polish, Russian, Czech, Arabic, …), review plural entries or use an LLM provider, which translates every form. See Plural Forms.

API limits¶

DeepL enforces per-request limits. TranslateBot handles batching automatically:

Max 50 texts per API request
Max 128 KB total request size

Character limits¶

The Developer plan's one-time credit covers 1 million characters, and Growth includes 12 million characters per year. TranslateBot's incremental translation (only translating new/changed strings) helps you stay within these limits.

DeepL vs LLM Providers¶

	DeepL	LLM (GPT, Claude, etc.)
Cost	Free tier available	Pay per token
Speed	Fast	Varies by model
Custom context	Not supported	TRANSLATING.md support
Terminology control	Via DeepL glossaries	Via TRANSLATING.md
Language coverage	30+ languages	Any language
Model selection	None needed	Many options

When to use DeepL

DeepL is a great choice when you want fast, high-quality translations without configuring an LLM provider, especially if your target languages are well-supported by DeepL and you don't need custom context via TRANSLATING.md.

When to use an LLM

LLM providers are better when you need custom terminology or tone guidelines via TRANSLATING.md, or when translating to languages not supported by DeepL.