Key takeaways
- Send the final version of the source: changes after translation starts are charged again and introduce errors.
- Editable source files such as Word, InDesign packages or XLIFF avoid the cost and risk of rebuilding scanned PDFs.
- W3C guidance, citing IBM, gives an average expansion of 200–300% for English strings of up to 10 characters translated into European languages.
- Text inside images, charts and videos must be supplied separately or it will be missed.
- Tell the provider the target market and variant, the purpose of the text and any terms not to translate.
This guide is for marketing, documentation, HR and product teams sending content for translation, whether a single Word file or a multilingual product launch. It sets out what to do before you request a quote so the translation is accurate, on time and easy to publish.
File preparation affects price and schedule directly. For how those are calculated, see translation cost per word in the UK and realistic translation turnaround times.
Why does file preparation matter for translation?
File preparation matters because translators work on the text you send, in the format you send it, and every problem in the source is multiplied by the number of languages. A missing image caption becomes ten missing captions; a late change becomes ten re-translations.
The Institute of Translation and Interpreting (ITI) makes the point in its buyer's guide Translation: Getting it Right: “having translators work from a draft-in-progress will almost always be more time-consuming — hence more expensive (and probably more frustrating) — than waiting for the final text to be ready.”
Which file formats are best for translation?
The best format for translation is the editable file the content was created in. Translation tools extract the text, protect the formatting and rebuild the file in the target language, which is only possible when the original is supplied.
| Content type | Send this | Avoid sending |
|---|---|---|
| Office documents | Word, Excel or PowerPoint originals | PDF exports or scans |
| Brochures and print | Packaged InDesign files with fonts and links (or IDML) | Flattened PDFs |
| Websites | CMS export, XLIFF or structured files | Copy-pasted page text |
| Software and apps | Resource files (for example JSON, XML, .strings, XLIFF) with context | Screenshots or spreadsheets without keys |
| Video | Script or subtitle file (SRT) plus the video | Video only |
| Official certificates | Clear, complete scan of every page | Partial phone photos |
If only a PDF exists, say so in the quote request. Converting a PDF back into editable form is possible, but it takes time and needs a layout check afterwards.
How much space should you leave for translated text?
Leave extra space for translated text, because most languages run longer than English, and short strings expand the most. The W3C Internationalization article on text size in translation publishes IBM's average expansion rates for text translated from English into European languages:
| Characters in English source | Average expansion |
|---|---|
| Up to 10 | 200–300% |
| 11–20 | 180–200% |
| 21–30 | 160–180% |
| 31–50 | 140–160% |
| 51–70 | 151–170% |
| Over 70 | 130% |
The W3C summarises: “The general message is that text will normally expand”. Buttons, menu labels, table headers and packaging panels are where this causes the most trouble. Design layouts that can grow, and avoid fixed-width text boxes. For software, see software localisation.
What reference material should you send with your files?
Reference material lets the translator match your terminology and tone from the first sentence. Send whatever you have:
- previous translations or a translation memory of related content (see what translation memory is);
- a glossary of approved terms and a “do not translate” list for brand and product names;
- a style guide covering tone, form of address and formatting (see translation glossaries and style guides);
- screenshots, product images or a link to the live site for context;
- the original-language source, if the text you are sending is itself a translation.
How to prepare files for translation: step by step
Follow these steps before you request a quote. They take little time and prevent most rework.
- Finalise the source. Get sign-off first; if changes are unavoidable, date each version and mark every change.
- Remove what is not needed. Delete outdated sections, internal comments and hidden text that should not be translated.
- Collect the editable originals. Package design files with fonts and linked images.
- Find text in images. List charts, diagrams, screenshots and photos containing words, and supply editable versions if you have them.
- Specify the target market. State the language and variant, for example Brazilian rather than European Portuguese, and the audience.
- Explain the purpose. Say whether the text will be published, printed, submitted to an authority or used internally.
- Mark what must not change. Brand names, product codes, legal entity names and quoted titles.
- Remove unnecessary personal data. If names, addresses or account numbers do not need translating, redact or anonymise them first.
- Use a secure transfer method. Send confidential files through the provider's secure channel, not as public file-sharing links; see data security when outsourcing translation.
Common mistakes when sending files for translation
The most expensive mistake is sending a draft and then a “final” and then a “final final”. Other common problems:
- Sending only part of the content. Footnotes, headers, alt text and pop-up messages are forgotten until review.
- Splitting sentences across text boxes. Languages change word order, so broken sentences cannot be translated properly.
- Building sentences from fragments in software. Strings such as “You have” + number + “items” cannot be translated grammatically into many languages.
- Not saying which variant is needed. “Spanish” or “French” is not a full specification.
- Editing translated files in-house without telling the provider. The next update overwrites your changes.
The wider selection and briefing process is covered in how to choose a translation agency.
How TranslationWorks can help
TranslationWorks is a UK-based translation agency that provides professional human translation by native-speaking linguists in 150+ languages, working with documents, websites, software and multimedia content for clients everywhere. TranslationWorks is certified to ISO 17100, the international standard for translation services. If you are unsure which files to send, share what you have and tell us how the translated content will be used, and we will tell you in your free quote what we need. TranslationWorks holds ISO 27001 registration and Cyber Essentials certification for handling confidential files. See our translation services and IT and gaming translation, or request a free quote within 24 hours.
