Dokumentace API
Registration page URL parameters
The registration page accepts query parameters that pre-fill the registration form. This is useful when redirecting users from your application — you can pass company and contact details so the user does not have to type them manually.
Example URL:
https://app.peppos.cz/register?name=Acme+s.r.o.&vatId=CZ12345678&email=info@acme.example.com
Accepted query parameters
| Parameter | Form field | Description |
|---|---|---|
| name | Company name | Pre-fills the company name field. |
| firstname | First name | Pre-fills the first name field. |
| surname | Last name | Pre-fills the last name field. |
| countryCode nebo country | Country code | ISO 3166-1 alpha-2 country code (e.g. cz, sk, de). Always lowercased. Both "countryCode" and "country" are accepted; "countryCode" takes precedence. If omitted, the country is inferred from the first two letters of vatId when vatId starts with two ASCII letters. |
| rn | Registration number | Company registration number (IČO / Handelsregisternummer). Used as the primary source for the registration number field. Falls back to the taxId parameter value if rn is not provided. |
| taxId | Tax ID | Domestic tax identifier (e.g. Czech DIČ without the country prefix). Stored separately and also used as a fallback for the registration number field when rn is absent. |
| vatId | VAT ID | EU VAT number including the country prefix (e.g. CZ12345678, SK2021234567). When countryCode / country is absent, the first two characters of the VAT ID are used to infer the country code. |
| phone | Phone number | Pre-fills the phone number field. Should include the country dialling code (e.g. +420608123456). |
| Pre-fills the email address field. |
Automatic company data lookup
When vatId or registrationNumber (rn / taxId) is provided together with a resolved country code, the registration page automatically looks up the company in the business register and pre-populates additional fields (address, legal name, VAT payer status). This enrichment runs silently in the background; existing pre-filled values are not overwritten.
- If vatId + country are present, the VAT ID lookup is tried first.
- If the VAT ID lookup returns no result (or vatId was not supplied), the registration number lookup is tried.
- If neither lookup finds the company, the form is still shown with the original query-parameter values.
Notes
- All values are trimmed. Empty or whitespace-only values are treated as absent.
- countryCode is always normalised to lowercase regardless of the input casing.
- Country inference from vatId only works when the first two characters are ASCII letters (a–z). Numeric-only or mixed identifiers are not inferred.