Terms of service

1. Service operator

fv.converts.ninja (the “Service”) is operated by Michał Mietliński SLUG IT, Pałucka 29, 60-604 Poznań, NIP 7811728934, CEIDG. Email: michal@mietlinski.pl.

These terms govern electronically supplied services. The Service is mainly intended for business or professional use, particularly by businesses and accounting firms.

2. Scope

The Service can create draft invoices and FA(3), manage numbering, retrieve and send KSeF documents, assign categories, run approvals, share confirmed invoices, prepare data for accounting systems including Comarch ERP Optima and create import files for payment orders supported by online-banking systems.

A payment file is neither execution nor authorisation of a transfer. The user must verify imported instructions in the bank and approve them under the bank's rules. The Service is not an accounting or tax-advisory service and does not guarantee tax correctness.

3. Technical requirements

An up-to-date browser with HTTPS, JavaScript and essential session cookies, plus a working email address, is required. KSeF features require valid authority and correct credentials for the relevant entity.

4. Account and access

Users are responsible for the email account used to sign in and for people granted company access. Multiple users and roles may belong to one company; sign-in codes must not be shared with unauthorised persons. Access or an operation may be temporarily blocked for security, abuse prevention, user protection or legal compliance.

5. KSeF and GUS

KSeF is an external public-administration system. The user is responsible for proper authority and deliberate submission to the correct environment. A KSeF-accepted invoice may have legal effects regardless of later activity in the Service.

Users may request public REGON data from GUS when adding a contractor and must verify it before use. The operator is not responsible for outages, changed limits, delays or errors in KSeF, GUS REGON or other external services, but designs the integration to handle ordinary communication errors and limits safely.

5a. KSeF monitoring and notifications

Users may enable automatic checks of received invoices and choose SMS, email or both. Messages can be sent when a selected condition is met or as a daily summary. Times selected in the settings use Polish local time.

The default allowance is 20 SMS messages per company per month unless the panel shows a different allowance. The Service administrator may increase the company's recurring allowance or grant an additional allowance valid only for the current month. A counter at the end of an SMS, for example “(2/20)”, shows the message's position and the total allowance available in that month. Email does not reduce the SMS allowance.

Notifications are an auxiliary feature. KSeF, email, SMS gateway, queue or network outages may delay or prevent delivery. A missing notification does not alter an invoice's KSeF status and does not replace the user's own checks of documents and deadlines.

6. User duties

Users must provide accurate data, review documents before approval and submission, comply with law and not supply unlawful content. Misleading documents, impersonation, bypassing safeguards, testing another person's account without consent and disrupting the Service are prohibited.

7. Drafts, approval and sharing

A draft is not sent automatically. Approval inside fv.converts.ninja and submission to KSeF are separate steps. Public sharing may be limited to invoices whose KSeF acceptance is confirmed.

8. Plan, fees and voluntary support

At present, each new company receives the same free plan with all released functions and no plan-defined invoice limit. Recording a start date does not create a payment obligation.

Future paid plans will state price, billing period, features, renewal and termination before selection. A free account never becomes a recurring paid subscription without the required consent. Voluntary support does not buy an SLA, development priority or individual support unless separately agreed; an external payment provider's terms also apply when used.

9. Availability and changes

The operator may maintain and update the Service for changes in KSeF, law, security, functionality or infrastructure. Planned work should minimise disruption where possible. No uninterrupted availability is guaranteed unless a separate SLA exists.

10. Liability

The user remains responsible for document content, tax treatment, deadlines, rates, contractor data, the submission decision and checking payment instructions before bank authorisation. Mandatory law governs operator liability. Where allowed in professional relationships, liability for lost profits and accounting decisions based solely on an automatic suggestion is excluded.

11. Data and security

Processing is described in the Privacy policy and safeguards on the Security page. Users must grant data access only to authorised persons.

12. Complaints and contact

Send comments or complaints to michal@mietlinski.pl, including the account address, company, problem and—where possible—document identifier or time. Never email KSeF tokens, private keys or sign-in codes.

13. Ending use

A user may stop at any time. Company-data deletion or account closure may require operator contact where retention, billing, security, claims or multiple organisation users are involved.

14. Company verification and abuse prevention

Entering a NIP does not prove authority to represent a company. A company may remain “Unverified” until successful production KSeF authentication for that NIP; test KSeF does not verify real-world authority.

Before verification, outward-facing features including KSeF submission, public sharing, bulk API use and invitations may be restricted and drafts marked unconfirmed. A company or operation may be blocked for suspected impersonation, misleading documents, safeguard bypass, automated abuse or other material security risk; this does not remove anything from KSeF.

15. Retention of unverified companies

A company never verified in KSeF for at least 90 days may be scheduled for deletion, normally with a further seven-day grace period. This may be extended for support, security or legal reasons. A previously verified company is not affected merely because its token or certificate later expires, is revoked or removed.

16. Deleting a user account

A user may request deletion in the Service. Memberships and sessions are revoked and the email is removed from the active profile. A sole owner must first transfer ownership or begin company deletion. Limited or anonymised audit information may remain where justified by integrity, security, law or claims.

17. Deleting a company

An owner may schedule company deletion after additional confirmation, currently with seven days to cancel. Deleting data from fv.converts.ninja does not delete invoices, entries or legal effects in KSeF or other external systems.

18. Vulnerability reporting

The operator may voluntarily reward a valid vulnerability report. Indicative amounts are not an unconditional promise; a decision depends on impact, quality, originality and compliance with testing rules.

19. Changes to the terms

These terms may change for a valid reason including law, KSeF, functionality, security or service delivery. The current version is published in the Service, and material changes affecting user rights should be communicated appropriately. Publishing a paid plan does not turn a free account into a paid subscription without consent.

20. Final provisions

Polish law applies to matters not covered here. Business-to-business disputes are resolved by the court competent under law unless the parties validly agree otherwise.