Do I need an interpreter for my webinar?

If a mistranslation would carry legal, financial or safety consequences, book a human interpreter. If the session is internal, informal or announced at short notice, AI translation or captions are usually enough — and often the honest answer is that you need neither.

The useful version of this question is not “can I afford an interpreter” but “what happens if a sentence comes out wrong”.

Book a human when the stakes are asymmetric

Hire an interpreter when a mistranslation costs far more than the interpreter does:

• Regulated or legal content — works council consultations, compliance training that people sign off on, anything a regulator could read back to you
• Contractual or financial commitments made live
• Safety-critical instruction
• Anything adversarial, where the other side benefits from ambiguity
• External audiences where the interpretation itself is the signal — a keynote to customers in their language says something about how seriously you take them

The common thread is that a human resolves ambiguity and an algorithm does not. An interpreter who hears a phrase that could go two ways picks the right one from context, or flags it. That judgement is what you are buying.

AI translation is usually enough when

• The session is internal
• It was announced at short notice — most interpreting needs two weeks’ lead time
• The content is repetitive and familiar: sprint demos, product updates, weekly all-hands
• Getting a sentence slightly wrong is recoverable — someone asks again
• You have more than two or three languages, where interpreter cost multiplies but AI cost usually does not

You may need neither

Worth checking honestly before spending anything.

If your audience reads the language fine and only struggles with spoken pace or accent, captions solve the real problem — and they help your native speakers too. If everyone genuinely works in one shared language and you are adding translation because it feels inclusive rather than because anyone asked, ask them first.

There is also a middle path that costs almost nothing: circulate slides and a written summary in each language before and after, and run the session in one. For information-dense sessions this often beats live translation, because people can read at their own pace.

The cost shape is different, not just the number

Interpreters are priced per language pair per session, with a minimum. Two interpreters per pair for anything over 30 minutes. Three languages means three pairs means six people. Cost scales with languages and duration, and there is a floor below which you cannot go.

AI translation is priced by usage. It does not care how many languages, and there is no floor — but there is no judgement either.

If you run one high-stakes session a quarter, interpreters are affordable. If you run fifteen internal calls a month across four languages, they are not, and the honest answer is that those fifteen calls currently happen in approximate English with nobody translating at all.

A decision in four questions

1. Would a wrong sentence create liability? → interpreter
2. Is it external and reputational? → interpreter, or do not translate at all
3. Is it internal and routine? → AI, or captions
4. Do people read the language but struggle to follow speech? → captions, and stop there