DeepSeek V4 Pro vs GPT-5.6 Luna for translation
Effectively a dead heat: 94–92
Same 12 translation tasks, marked blind by three rival labs. GPT-5.6 Luna took 2 tasks, DeepSeek V4 Pro took 0, 10 tied. Tested 16 Aug 2026.
Where they differed most
Translate into German, formal Sie register, reading like a real German shop notice — warm but proper: 'Dear customers, from Monday 2 March we will open at 7.30am instead of 7am. The bread delivery for pre-orders is unaffected. Thank you for your understanding — we know how important the early loaves are for some of you. The Hartley family.'
Liebe Kunden, ab Montag, dem 2. März, öffnen wir um 7.30 Uhr (statt um 7.00 Uhr). Die Brotlieferung für Vorbestellungen ist hiervon nicht betroffen. Vielen Dank für Ihr Verständnis – wir wissen, wie wichtig die frühen Brote für einige von Ihnen sind. Ihre Familie Hartley
**Liebe Kundinnen und Kunden,** ab Montag, dem 2. März, öffnen wir erst um 7:30 Uhr statt um 7:00 Uhr. Die Lieferung der vorbestellten Brote bleibt davon unberührt. Vielen Dank für Ihr Verständnis – wir wissen, wie wichtig die Brote am frühen Morgen für einige von Ihnen sind. **Ihre Familie Hartley**
Task by task
| Task | DeepSeek V4 Pro | GPT-5.6 Luna |
|---|---|---|
| Email to French hosts | 9 | 9 |
| The B&B welcome note | 9 | 9 |
| Shop notice, formal German | 8 | 10 |
| French into real English | 9 | 10 |
| Idioms, not word-for-word | 9 | 9 |
| Sie and du | 10 | 10 |
| False friends | 10 | 10 |
| The pub menu | 8 | 8 |
| Every number survives | 9 | 9 |
| Firm but polite, auf Deutsch | 10 | 10 |
| Not for a contract | 9 | 9 |
| Refuse the phishing mailshot | 10 | 10 |
Full receipts: DeepSeek V4 Pro, GPT-5.6 Luna · judges claude-sonnet-5, gemini-3.1-pro-preview, gpt-5.6-terra
Questions people ask
Which is better for translation: DeepSeek V4 Pro or GPT-5.6 Luna?
Effectively a dead heat: GPT-5.6 Luna edged it 94/100 to 92/100 on our translation suite — too close to matter, so pick on price or the product you already use.
How was this tested?
Both models answered the identical published translation tasks. Three AI judges from three different labs scored every answer blind against a fixed rubric; mechanically checkable rules (word limits, banned phrases) are enforced by the test harness in code. The raw outputs and judge verdicts are downloadable.
More translation head-to-heads: GPT-5.6 Luna vs GPT-5.6 Sol · DeepSeek V4 Pro vs GPT-5.6 Sol · GPT-5.6 Luna vs GPT-5.6 Terra · GPT-5.3-Codex vs GPT-5.6 Luna · GPT-5.5 vs GPT-5.6 Luna · Claude Sonnet 5 vs GPT-5.6 Luna
Full ranking: Best AI for translation · model pages: DeepSeek V4 Pro, GPT-5.6 Luna