SaaS / business softwareAI productsOriginal by DeepL
DeepL won professionals' trust with natural, fluent translations. Users paste text or translate Word, PowerPoint and PDF files without breaking the formatting, choose formal or informal address and switch to alternative words with one click. Company-specific glossaries make sure the same product name is translated the same way in every document. A promise not to store data and strong security commitments form the foundation of enterprise sales.
To build something similar you need a translation engine (open-source translation models, fine-tuned LLMs or translation APIs), a format-preserving document-processing pipeline, glossary management, web and desktop apps, a developer API and an enterprise admin panel. A quality edge can be created in particular language pairs and industries; for example, specialising in legal, medical or e-commerce translation for a specific language pair is a strong position.
How DeepL works: the core user flow
How many apps and dashboards do you need?
Web and desktop app
The translation interface for text and documents, summoned from any app with a shortcut.
Developer API
The usage-based API and documentation portal that software uses for automatic translation.
Enterprise admin panel
The panel for managing team users, glossaries, usage quotas and security settings.
Critical features of a product like DeepL
Format-preserving document translation
Word, PowerPoint and PDF files are translated while keeping the layout of tables, headings and images.
Glossary
Equivalents for company-specific terms are defined, and the engine always uses them the same way.
Formality and tone choice
Formal or informal address and the level of formality are selected, and the translation is tuned to the audience.
Alternative suggestions
Clicking a word shows alternatives, and the choice automatically adapts the rest of the sentence.
Quality and language-pair optimisation
Priority language pairs are fine-tuned with domain data, and automatic quality metrics are monitored.
Enterprise data security
Texts are deleted after translation and transmitted encrypted, processed in line with GDPR and corporate security requirements.
What goes into the first version, what comes later
First version (MVP)
- Text translation and language detection
- High-quality translation for priority language pairs
- Word and PDF document translation
- Freemium plan and subscription
- Word alternatives
Later releases
- Glossary and enterprise panel
- Developer API with usage-based pricing
- Desktop app and browser extension
- AI writing assistant and voice translation
Modules and how the budget is calculated
The budget is calculated with 360 SOFT’s pricing model from the modules below, about 18 screens and the project’s complexity: roughly 69 person-days for the full scope and 44 person-days for the first version. Every module you drop lowers the budget directly.
| Module | Phase |
|---|---|
| Sign-up, login, social login | First version |
| User profile and settings | First version |
| Roles and permissions | First version |
| Admin dashboard | First version |
| Subscriptions and recurring billing | First version |
| Online payments (Stripe / PSP) | First version |
| AI features (LLM, RAG, recommendations) | Later release |
| File, photo, video upload | First version |
| Multi-language | First version |
| GDPR and security hardening | First version |
| Third-party API integration | First version |
| Reporting and analytics | Later release |
Hosting, SMS, map APIs, app store accounts and payment-provider fees are separate items. Maintenance and improvements (optional): €250 / month. We send a fixed written price within 24 hours after a free discovery call.
The hard parts
Translation quality
Being clearly better than general translation services is hard, and data and evaluation are constantly needed for the chosen language pair and domain.
Document formatting
In complex PDFs and presentations, layout breaks when text length changes, so format preservation is its own engineering task.
Compute cost
Long documents and API traffic demand high processing power, and model optimisation and efficient hosting determine cost.
Business model
In a freemium model, free users work with character and document limits; paid individual plans offer unlimited text, more documents and glossaries. Team plans are priced per seat. The developer API is a separate revenue line charged per character. Enterprise customers can be offered annual contracts with data security and custom model tuning.
Get a free quote for your project
Let us scope it together and send a fixed written quote within 24 hours. NDA on request; you own the source code.
Choosing a company to build an app like DeepL
Most people searching “build software like deepl” are really looking for a reliable app development company. When comparing quotes, check four things:
- Can you try similar products they have shipped, in the stores or live?
- Are the source code, design files, servers and store accounts transferred to you by contract?
- Do they show a working demo every two weeks, with written scope and acceptance criteria?
- Are maintenance, scaling and GDPR/security costs written into the quote?
Copyright and trademarks
A business model and features are generally not protected on their own, but the DeepL name, logo, interface design, content and source code are. That is why we build a product with similar functionality but your own brand, design and code. This is not legal advice; we recommend a trademark search before launch.
Frequently asked questions
How long does it take to build software like DeepL?
A first release offering text and document translation with ready-made translation models or APIs can be ready in a few months. Fine-tuning models and evaluating them for superior quality in specific language pairs is a long-haul process.
Do I need to train my own translation model?
At the start, open-source models or LLMs may be enough. To stand out in a specific industry and language pair, fine-tuning on your own parallel data is an effective route.
Will there be copyright or trademark issues?
The AI translation business model is generally free to use; however, the name, logo, interface design, copy and code cannot be copied. The licence of the training data also needs attention; this is not legal advice.
What should I look for when choosing a company to build translation software?
Choose a team with experience in machine translation, document processing and model hosting. Ask which metrics they use to measure quality and how they ensure data security.
