Machine vs Professional Translation: When to Use Each

Current State of Machine Translation

Neural Machine Translation (NMT) has made a breakthrough over the last 5 years. DeepL, Google Neural Machine Translation, and Yandex Translate use transformer-based models that consider the context of an entire sentence and even paragraph. Quality for European language pairs (English-German, English-French) approaches 85–90% on BLEU metrics.

But metrics are averages. They mask critical failures: a machine can translate 9 out of 10 sentences flawlessly and make an error in the tenth that inverts the document's meaning.

When Machine Translation Is Acceptable

Gisting. An employee needs to understand the gist of a foreign partner's letter or browse an international article. Wording precision isn't critical — general meaning matters. MT handles this well.

Internal correspondence. Corporate chats, internal instructions, memos — if the document stays within the company, machine translation saves time.

Initial screening of large volumes. A company needs to review 500 pages of technical documentation and select 50 relevant ones. MT allows quick filtering, with professional translation ordered only for selected sections.

User-generated content. Marketplace reviews, social media comments, support tickets — rough translation is acceptable there.

When Machine Translation Is Unacceptable

Legal documents. Contracts, corporate charter documents, court decisions. A single mistranslated modal word (shall/may/will) changes the parties' obligations. MT regularly confuses these constructions.

Medical documents. Drug instructions, clinical trial protocols, discharge summaries. An error in dosage, active ingredient name, or contraindication can endanger a patient's life.

Notarized documents. Certificates, diplomas, government documents. A notary certifies a qualified translator's signature — machine translation cannot be notarized.

Marketing and advertising materials. A machine-adapted slogan at best sounds awkward, at worst offends the target audience. Cultural adaptation is beyond MT's capabilities.

Patent documentation. Patent claims are legally significant text. An imprecise translation narrows or broadens the scope of patent protection.

PEMT: The Compromise Option

PEMT (Post-Editing of Machine Translation) is machine translation edited by a professional translator. Two levels:

• Light PEMT — quick editing: fix gross errors, verify meaning. Suitable for informational materials, technical descriptions. Cost: 50–60% of full translation.
• Full PEMT — deep editing: style, terminology, grammar, natural flow. Result comparable to professional translation. Cost: 70–80% of full translation.

We offer PEMT for technical texts of 50+ pages where the savings are substantial. For legal and medical documents, we do not use PEMT — the risk doesn't justify the savings.

MT Engine Comparison: DeepL, Google, Yandex

Based on our internal assessment (2,500 test segments, 8 language pairs, 2024):

• DeepL — best results for European pairs (EN-DE, EN-FR, EN-ES). Natural style, good context handling. Weaker on Asian languages.
• Google Translate (NMT) — widest language coverage (130+). Consistently average quality. Best choice for rare language pairs.
• Yandex Translate — best results for RU-EN and RU-DE pairs. Handles Russian syntax well. Limited language set.

None of the engines provide consistent quality for legal, medical, or highly specialized terminology. In every test, 10–15% of segments contained critical errors.

How to Choose: Client Checklist

1. Will the document be used outside the company? Yes → professional translation.
2. Could an error lead to financial or legal consequences? Yes → professional translation.
3. Does the document require notarization? Yes → professional translation only.
4. Volume over 50 pages, technical subject? Consider PEMT.
5. Internal use, general understanding? MT is acceptable.

Not sure which option fits? Send the document to us — we'll assess complexity for free and suggest the optimal solution. Written translation from 450 ₽/page, PEMT from 250 ₽/page. Contract-based, simplified tax system (no VAT), closing documents provided.