Copilot in Dutch
Copilot in Dutch: what works and what doesn't.
Copilot speaks Dutch. Just not as well as English, and not the same way everywhere. Below: where the difference sits, where it gets in your way, and what to do about it.
Why Dutch behaves differently
01 · The cause
A language model is not a dictionary. It predicts what probably comes next, and that probability rests on far more text in English.
You notice that difference not in the facts but in the phrasing. Ask for a summary of a meeting and the content is right; ask for an email to a colleague and you get something that reads like a translated American memo. Words pile up, sentences get longer than anyone would write themselves.
The second difference is register. Dutch draws a sharp line between informal and formal address, and between spoken and written language. Without instruction Copilot almost always picks the formal side. That may be right for a letter to a citizen, and it is almost always wrong for a Teams message to your own team.
The third difference is the most treacherous: compound words. Dutch glues concepts together where English uses spaces. Copilot regularly splits them wrongly or invents a compound that doesn't exist. In running text you notice; in a list of headings or an Excel column you don't.
The limit
What's written here is a snapshot. Microsoft improves Dutch output with every model version, without telling you. So don't assume a test from six months ago still holds.
Where it holds up
02 · Strengths
Summarising
Meetings and long email threads
Summarising a Dutch-language Teams meeting is reliable. The content is right, the action points usually are, and who said what comes out correctly in the vast majority of cases.
Rewriting
Making your own text shorter
When you supply the text yourself, the Dutch of the result is good: the model has your tone to hold on to. Rewriting therefore works better than writing from scratch.
Analysing
Asking questions of data
A Dutch question about an Excel table produces a correct analysis. Language hardly matters here: the calculation isn't in the language but in the formulas generated underneath.
What to do about it
03 · In practice
01
State the tone explicitly
"Write informally, short sentences, no filler connectives." Three lines up front save more than ten rounds of correction afterwards. Put them in a block of text you reuse.
02
Supply the source
Point to an existing document in your own style instead of describing the style. An example works better than an instruction, and it saves you describing something you find hard to put into words.
03
Check the compounds
Go through headings, bullet lists and column names separately. That's where the errors sit that you'd catch in running text but miss in a list. It takes two minutes and it's the most common blunder.
04
Never trust jargon blindly
Sector- and organisation-specific abbreviations get explained wrongly, with confidence. If you can't verify the term yourself, you can't use the answer. That's not a shortcoming of Copilot but of the task.
05
Pick your language per task
Dutch for anything going out in Dutch. English when you're analysing English-language sources and will edit the result anyway. Not dogmatic, but deliberate.
06
Turn it into agreements
An organisation where everyone enforces their own tone gets fifty different house styles back. One shared prompt rule in a reference everyone may read solves that.
Questions about Copilot and Dutch
04 · Frequently asked
Does Microsoft 365 Copilot work in Dutch?
Yes. You can type Dutch and get Dutch back, in every Office app and in Copilot Chat. The interface language follows your Microsoft 365 setting; the answer language follows the language of your prompt. Ask something in Dutch about an English document and you usually get a Dutch answer about English content.
Is Copilot's Dutch as good as its English?
No, and that isn't an opinion. The difference is mostly tone and idiom: Dutch output more often reads as translated, uses longer sentences and reaches for phrasings that are normal in English but stiff in Dutch. Factual reasoning and summarising hold up equally well.
Why does the Dutch sound so formal?
Because the model has seen far more English than Dutch, and because the Dutch it saw is more often written than spoken language. Without instruction it picks the safest registers: formal address, long sentences, nominal style. You fix that by stating the tone explicitly, not by hoping for better.
Can Copilot follow our tone of voice?
Within one conversation, yes, if you supply the rules or point to a document containing them. Across conversations, no: Copilot doesn't remember your tone of voice on its own. In practice a fixed block of text you paste in works better than explaining it every time.
So should I just prompt in English?
For a Dutch end result, rarely. You gain a little accuracy and lose the nuance of your own professional vocabulary, and you still have to translate, which introduces new errors. For complex analysis of English-language sources, prompting in English can help.
Does Copilot recognise Dutch jargon and abbreviations?
It varies. General terms are fine. Sector- and organisation-specific abbreviations, a benefits decision, a registry object, your own project codes, are regularly misexplained, and usually without any hedging. That is exactly where judging the output comes in.
Read on
- How does Copilot actually work?
Where the answers come from and why it sometimes makes things up.
- The Copilot training
Eight modules covering prompting skill and judgement separately.
- Copilot for communications
For teams producing Dutch copy all day long.
Language can be learned. So can judgement.
The training has one module purely on prompting skill and one purely on judgement. The second is where most of the potential gain is left on the table.