Quality at tolingo How we keep translation quality consistent
Quality at tolingo means matching the level of checking to what a text is for. Our highest level is the four-eyes principle to ISO 17100, where a second specialist independently revises the translation; lighter levels use machine translation with post-editing by a single specialist. Whichever you choose, you get 35 days after delivery to ask for corrections on any specialist translation, not the usual 14.
Four ISO certificationsMore than 140,000 clients have trusted tolingo since 2007
- Certification: four ISO standards, checked by TÜV Süd (ISO 9001 since 2016, ISO 27001 since 2018) and LinquaCert (ISO 17100 since 2015, ISO 18587 since 2022). Annual re-certification; certificates available to download.
- Translators: native-speaker specialist translators with a degree in translation or at least five years' experience. Vetted in advance, grouped into dedicated language teams.
- Checking levels: from machine translation with post-editing by one specialist (two eyes), up to the four-eyes principle to ISO 17100, where a second specialist revises. We match the level to the text; your account manager helps you choose.
- What you get: documented processes, certificates to download, one dedicated contact per account, encrypted data transfer, EU servers, and 35 days to request corrections on every specialist translation.
In detail
Certificates, translators and cases
If you want to go deeper, each part of the quality system has its own page. Three places to start:
What the four ISO standards cover, how audits work and what evidence we provide.
Who works for tolingo: qualifications, selection, dedicated language teams and fields.
Connox (e-commerce), HR7 (staffing) and Becker Sonder-Maschinenbau on working with tolingo.
The four ISO standards, and what each does for you
What each standard covers in practice
A single ISO standard says little on its own. It is the combination that makes a complete quality system. ISO 17100 sets out how a translation is produced. ISO 9001 makes sure that process is followed across every department. ISO 27001 protects your documents while they move through our systems. ISO 18587 covers the special case of machine translation followed by human post-editing. At tolingo, TÜV Süd checks the company-wide systems (ISO 9001, ISO 27001), and LinquaCert the translation-specific standards (ISO 17100, ISO 18587).
The core standard for professional translation, held by tolingo since 2015. It requires qualified translators, the four-eyes principle through a second specialist, documented project management and feedback loops with the client. What that means for you, when you choose an ISO 17100 translation: translation plus revision by two different native-speaker specialists, documented so it can be shown. More detail on the certificate page: ISO 17100.
The standard for machine translation post-editing, held since 2022. It governs how qualified post-editors rework machine-translated text so the result is fit to publish. What that means for you: standardised MTPE workflows from €0.05/word, worth considering for high volumes with a lower risk profile. More on this: our post-editing page.
The overarching standard for quality management systems, held since 2016 and audited each year. It calls for a process-oriented approach, continuous improvement, documented procedures in every department and regular audits. What that means for you: consistency in the translation and at every other point of contact with tolingo, from quote and project management to complaints and billing.
The international standard for information security management systems (ISMS), held since 2018. In the translation industry, tolingo was an early adopter. It governs the physical, technical and organisational measures that protect confidential data. What that means for you: encrypted data transfer, EU servers, documented access rights and a signed NDA from every translator. More on this: certifications.
The current ISO certificates from TÜV Süd and LinquaCert are on the certifications page, ready to download. Suitable as an annex for tenders, supplier approvals and internal compliance reviews.
The four-eyes principle in practice
What happens to your document along the way
Not every text needs the same depth of checking, so we work in levels. The dividing line is simple: two eyes means one qualified specialist works on the text; four eyes means a second, independent specialist checks it afterwards. The four-eyes principle is the core method in ISO 17100, and it is the level we recommend for anything you publish or that is regulated. It is not automatically part of the lighter, machine-translation-based levels, which exist for speed and volume.
| Level | What happens | Review | Typical use |
|---|---|---|---|
| AI translation | Machine translation, then a specialist post-edits the essentials (Light Post-Editing) | Two eyes (one specialist) | Internal use, gist, high volume |
| SMART | Machine translation, then a specialist fully post-edits it to read as if written by a human (Full Post-Editing) | Two eyes (one specialist) | Idiomatic text on a tighter budget or timeline |
| ISO 17100 | A specialist translates, a second independently revises: the four-eyes principle | Four eyes (two specialists) | Anything published or regulated |
| PREMIUM | A specialist translates, a second edits for style and complex briefs | Four eyes (two specialists) | High-stakes, brand-critical content |
Your account manager recommends the level that fits the text, rather than charging you for a second specialist you may not need. When you choose an ISO 17100 (four-eyes) translation, here is how it runs, step by step:
- Project management
Your brief, terminology rules and glossaries are stored in the system. For recurring work, a translation memory is switched on.
- Translation
A native-speaker specialist translates the text into their first language, working in the field their qualifications cover.
- Revision
A second native-speaker specialist reads the target text against the source (bilingual review), checking linguistic accuracy, consistency, terminology and completeness.
- Quality assurance
Automated checks for numbers, date formats, brand names and glossary adherence. For data-sensitive texts, an extra review.
- Delivery
In the format you want (DOCX, XLIFF, JSON, PDF, InDesign package). With DTP adjustment if you need it.
For especially sensitive content (legal texts or medical documents, say), we offer a third editing stage on request. It isn't included by default, because it raises the price noticeably.
In their words
What partners say about working with us
“I'm really impressed. What I like most is the very friendly, personal service and the high quality of the translation.”
“What stands out is the flexibility on out-of-the-ordinary projects. tolingo is open to creative solutions too.”
“We're very happy with both the service and the account support. tolingo is reliable and, above all, on time.”
What your buying team actually gets
Answers for compliance, IT, procurement and the department
In most companies, no single person decides on a translation partner. A selection of the most common questions by role:
ISO certificates to download as PDFs on the certifications page. Documented processes for tenders and supplier approvals. A template NDA is available. Certified translations are handled through Juristra for companies.
ISO 27001-certified information security management. Encrypted data transfer, EU servers, role-based access rights. GDPR-compliant translation processes. API connection available.
Transparent per-word prices: MTPE from €0.05, specialist translation from €0.12. Framework agreements available. One dedicated contact per account. A translation memory cuts the cost of repeated content by up to 70%.
Native-speaker specialists for each language and industry. Consistent terminology through terminology management. For marketing content, transcreation is available too. Express in 24 hours is possible.
Three firm commitments
35-day correction window, 10-minute reply, one contact
Three things we commit to contractually. Not marketing promises, but part of our standard process.
On every specialist translation to ISO 17100. If you report substantively justified changes within 35 days of delivery, we correct them at no extra charge. The industry norm is 14 days.
Our project management acknowledges every enquiry within 10 minutes during business hours. For clearly defined jobs, the full quote comes the same working day.
One direct contact in project management per account. You know who is responsible, and you have their direct line and email. No anonymous ticketing system.
Common questions about quality
Audits, liability, the four-eyes principle & the correction window
Ready to look into working together?
If you have specific volumes, languages or fields in mind, we'll put together a quote within ten minutes. For tenders, we send the ISO certificates as PDFs up front.
Reply in 10 minutes · ISO 17100 · ISO 27001 · 35-day correction window