Give your software e-invoicing ability

picture showing e-invoices online transformation api machine
  • Data to e-Invoice transformation in seconds
  • Delivery to any clients and tax authorities
  • e-Invoices available for 48h list item

Integrate our API for data to e-invoice transformation

Get compliant
e-invoicing with 1 API key

Integrate our API key that will send invoice data to our service and create an e-invoice

Skip development of e-Invoicing component

Instead of complex development and testing period to prepare electronic invoicing ability, integrate the API calls into your software.

Your brand across entire customer experience

We will be hidden partner for your invoicing backend.

Ensures tax and legal compliance forever

We take care of all future legislation changes so you can forget about them completely - forever.

Sign up and get 100 free transformations

With our API, invoice data will be transfomed into e-invoices. Skip all development and provide your software with e-invoicing ability in days.

How to start?

By integrating our API you spend a fraction of the cost and time neccessary to develop full invoicing/e-invoicing/fiscalization functionality.


Register for free

When registering choose to register you company as Transformer.


Integrate our APIs

With our instructions integrate transformation APIs and test the solution.


Add your customers

Add your customers manually/via API and get connection keys for them.

Start transforming!

Set the creation/sending flow as you like.

Congratulations, your software just got the ability of e-invoicing!

Quick and easy integration

See the API documentation

Send one invoice or a mass of them in one request.

One to one

Invoice data is prepared in the form of a simple JSON object. Get XML online or download it later with sent Id.

Get documentation

Mass API

Bulk upload of invoices' data in the form of a .CSV file. The response includes a list of IDs for later download.

Get documentation

Coming soon!

How does it work?

  1. Data (from your software) is taken and .JSON file is created and send to e-Invoices Online by calling 1 simple REST API
  2. e-Invoices Online transforms the received data into a detailed e-Invoice
  3. The e-Invoice can be sent to SEF and/or (automatically) downloaded.
  4. e-Invoice is kept on our server for 48h, before being deleted. It can be edited inside of your account. (Archiving?)* 

*All invoices are legally required to be archived for a determined number of years (differs between countries). Should you wish to have the legal archive included in your package, consider taking the Integrator package.

Save months of development time

Use cases

Invoicing provider

You have put a great deal of time and effort into developing your invoicing software and building a customer base. Now, there is a new Government-imposed e-Invoicing requirement that would take you more time and effort to develop. Save your time and money for more important matters, and let us provide you with the e-Invoicing component you’re missing.

DMS or EDI provider

You provide a comprehensive service that has a large overlap with the requirements of a full e-Invoicing system. The document exchange and archiving are key aspects to both services. You likely have clients that would benefit greatly from e-Invoicing. So rather than them seeking this service elsewhere, upgrade your service by adding our e-Invoicing component to your existing infrastructure.


You are looking to develop a service/product that includes e-Invoicing, but wish to maintain full control of your customers’ experience throughout your service. Instead of redirecting your clients to an external e-Invoicing service, the Transformer package allows you to use our service as a hidden partner. Your software can rely on our service, all while never being seen by the customer.

Accounting software

You have a software for accountants that is serving them completely but your software is lacking the e-invoicing functionality. Keep focusing on providing the best solution for accountants but let the e-invoicing legislation to us. Integrate in days instead of lengthy development.


One time set-up fee + package. Choose a payment period and quantity of transformations per month.

EUR 1000 /set-up

Quantity :


naplaćuje se godišnje
payed monthly



Transform&send first 100 invoices for FREE

Transform up to 100 invoices to e-invoices and deliver to Tax Authority Portal.

payed annually
payed monthly



Transform an invoice to e-invoice (Peppol BIS or country specific)

Start for free Cancel anytime
EUR 23.490 /year
2349 EUR 1957 /mo.
EUR 12 /mo.
payed annually
payed monthly



Transform an invoice to e-invoice (Peppol BIS or country specific)

Send to TAP (Tax Authority/State portal) - domestic delivery

Start for freeCancel anytime
EUR 58.810 /year
5881 EUR 4900 /mo.
payed annually
payed monthly

TR. & SEND & P


Transform an invoice to e-invoice (Peppol BIS or country specific)

Send to TAP (Tax Authority/State portal) - domestic delivery

Send to Peppol network - international delivery

Start for free Cancel anytime

Transformation is a service for any software development company that allows you to simply transform invoices into electronic invoices, by integrating our APIs into your software. Additionally, we offer domestic delivery to tax authority portals and/or international delivery via the Peppol network. We give your software full electronic invoicing ability.

You send invoice data, in the form of a simple .JSON file, from your software to our service via API. Using that data, we create an e-invoice. Once the e-invoices are transformed (into a country-specific or EU Peppol BIS 3.0 standard), they are immediately delivered back to your software and remain available in our service for 48 hours. With an additional API, we can also arrange the e-invoice to be delivered to any domestic tax authority portal and/or the Peppol network for international invoices.

Yes! See just how easy implementing our APIs is by downloading the documentation for “one-to-one” or “mass” API transformation.

After signing up, you can add all your customers via API. You can track how many e-invoices they send into transformation, which customers cost you the most, ... etc.

Once you sign up, you receive 100 free e-invoice transformations, which you can use for testing the service.