DeepL, ChatGPT or a human translator: how to choose based on the document<\/h1>
DeepL, ChatGPT or a human translator? The short answer is that it depends on the document. For internal, urgent or throwaway texts, machine translation will do the job. For anything that represents your company \u2014 your website, a contract, a technical manual or a campaign \u2014 you need professional human review. At Overseas we combine both: AI translation and human post-editing, backed by the ISO 17100:2015 certification we have held since 2017, depending on what each project needs.<\/p>
Each option in a nutshell<\/h2>
Before you choose, it helps to know what each tool does, because they are not in the same league.<\/p>
DeepL is a neural machine translation engine: fast, fluent and particularly good between European languages, although it translates without understanding your context or your industry.<\/p>
ChatGPT is a large language model (an LLM): give it instructions and it translates with a great deal of flexibility in tone and style, but it can be inconsistent and sometimes makes up what it doesn’t know.<\/p>
A professional human translator translates and adapts the message to your industry, your brand and your customer, and is accountable for the quality of the final result.<\/p>
And there is a fourth route, the one we use most on a day-to-day basis: post-editing. AI translates first, then a professional translator reviews and corrects the output. We explain this in detail in our article on AI translation with human review<\/a>.<\/p> There is no outright winner. Each option has its own territory, and combining them well is precisely what an agency does.<\/p> This is the decision that really matters. Instead of asking yourself “which is better?”, ask “what’s at stake if this goes wrong?”. Ask that, and the choice practically makes itself.<\/p> For emails, internal notes and drafts where you just want to get the gist of a text, use DeepL or ChatGPT directly. Speed comes first, job done.<\/p> For large volumes of internal documentation, such as an intranet or training materials, AI with light post-editing is a good fit. You cut costs and the text stays clear and useful.<\/p> For your website, brochures, campaigns and anything marketing-related, use a human translator. Here you don’t translate words, you translate intent, and that is something a machine still can’t do.<\/p> For technical manuals, product data sheets or tender specifications, use specialised human translation or AI with full post-editing. A technical error in a manual isn’t a typo: it can cost money or create a safety issue.<\/p> For contracts and legal or administrative documents, always use a human translator. A machine can mistake an obligation for a recommendation, and there is no margin for error here.<\/p> When the text leaves your company and goes to a customer, an authority or the market. AI translates fast, but it doesn’t know that a nuance in a contract shifts the entire liability, or that your product name shouldn’t be translated.<\/p> Here’s an example we see all the time: a technical data sheet where the same term is translated two different ways on two different pages. AI sees nothing odd about it and signs it off. A reviewer spots it, and also knows which term is correct in your industry. In an installation manual, that difference is what separates a professional document from one that causes confusion on site.<\/p> The industry itself confirms this. According to Slator, between 90% and 98% of those using machine translation or LLMs apply some level of human review to the output. In other words, hardly anyone publishes machine output without a professional going over it.<\/p> AI in translation is already part of the industry’s daily routine. It’s the foundation almost all of us work on. According to CSA Research, 90% of large companies already use AI-assisted translation solutions. And post-editing is no longer a niche: Nimdzi estimates that its adoption rose from 26% in 2022 to almost 46% in 2024.<\/p> What hasn’t changed is who makes the call. AI speeds things up; the person (the professional) decides what works and what doesn’t.<\/p> We don’t choose between AI and human from the outset: we use whatever each project needs. For large volumes with no brand nuances, AI translation and post-editing. For your website or a contract, a native translator specialising in your industry. On post-editing projects we also apply the criteria of ISO 18587:2020, the standard specific to post-editing, as industry best practice.<\/p> We work with native translators by sector \u2014 engineering, construction, materials, transport \u2014 backed by the ISO 9001:2015 and ISO 17100:2015 certifications we have held since 2017. More than thirteen years in this business have taught us one simple thing: what’s cheap today ends up being expensive if it has to be redone.<\/p>What is each one best at?<\/h2>
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<\/a><\/h2>Which tool for which document?<\/h2>
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<\/a><\/h1>When shouldn’t you leave it to AI alone?<\/h2>
What the industry is doing<\/h2>
How we do it at Overseas Translations<\/h2>