Terms of service
This English version is a translation provided for information. Only the Hungarian text is legally binding: the Hungarian original.
What adatka provides, what it does not promise, and what we ask in return. One page, without legalese — but binding.
In force: 20 September 2026 · Amendment: 21 September 2026 — section 5: use by querying, and the prohibition on copying out the entire dataset; section 6: Magyar Posta Partner Extra as a source. · Amendment: 23 September 2026 — section 6: the Magyar Posta layer made live. · Language correction: 24 September 2026 — the reader is addressed uniformly as “Ön” (the formal “you”); the content of the terms did not change. · Clarification: 24 September 2026 — description of the list of sources: it applies to the response as a whole, not field by field. · Amendment: 25 September 2026 — section 3: the description of the service; section 4 revised (beta and availability; a missing match does not prove that the address does not exist); section 6 revised (the results and the source licences). · Amendment: 30 September 2026 — section 1: the operator's current legal status, and how the operator's name and place of residence can be requested in order to enforce a legal claim; section 8: access to earlier versions; section 9 revised (new title: Applicable law and disputes): mandatory protection of consumers, amicable settlement with a 30-day response time (not a precondition for going to court), the condition for launching a paid service, the courts in Hungary and the order for payment, provision of the operator's name and place of residence within 8 days. · Clarification: 2 October 2026 — section 4: returning the floor and door as entered. · Material amendment: published 3 October 2026, takes effect 2 November 2026 — section 8 revised: for what reasons we may amend the terms, what counts as a material change, 30 days' prior notice on the home page and, to those who have an API key, by email, what continued use means, the earlier versions, transfer of the service to another operator, the rules on termination by notice and on termination; section 5: personal data other than the address that must not be sent, communication of the API key's limits, and that if you send the address or coordinates of another natural person, you are the controller and we are the processor with respect to those data; new annex: Data processing terms; section 7: liability for the processing of personal data; section 9: data protection lawsuit in another Member State of the European Union; sections 1 and 4: reference to section 8. · Material amendment: published 5 October 2026, takes effect 5 November 2026 — section 5: the numerical quota for use without a key (a reserve of 60 requests per IP address, refilled at two requests per second, at most 3,000 requests per day; each row of /clean is one request); until then, an anti-abuse brake under section 5. The numbers and the description of the 429 response are in the “Limits” section of the API documentation.
1. Who you are contracting with
With the operator of adatka.hu. The operator is currently a private individual: the operator runs adatka.hu neither as a sole trader nor through a company. We do not publish the operator's name and place of residence on the site; if you need them in order to enforce a legal claim against the operator, we provide them in the manner described in section 9. What changes when the service is provided by a sole trader or a registered company is described in the Legal notice and in section 8.10 of these terms.
The service is free of charge. There is no fee, no invoice and no subscription. When a paid plan is launched, this will happen by amending these terms, with advance notice in accordance with section 8; we may charge a fee only on the basis of your express acceptance (section 8.7).
2. When the agreement is concluded
When you start using the site or the API. No separate click of acceptance is needed for these terms to bind you.
3. What the service provides
- completing addresses as you type;
- breaking down an address given as free text into a structured form;
- finding the nearest address on the basis of coordinates;
- KSH codes and coordinates for the matches.
4. Beta and availability
The service currently operates as a free-of-charge beta. We aim to run it continuously and reliably, but for now we do not commit to guaranteed availability or a fixed time for resolving faults. Temporary outages may occur because of maintenance or technical faults, and the features and response formats may change in the course of development; if such a change is material under section 8.2, we will give advance notice of it in the manner described in section 8.4.
The operator does not guarantee that the data sources are complete, accurate or up to date. A match is not an official certificate.
Floor and door are not checked. The response returns the floor and door as entered in a separate field, but such data does not appear in the open sources, so we do not check it.
If a house number does not appear in Adatka's data sources, this does not prove that the address does not exist. Therefore, do not use Adatka in such a way that a missing match automatically prevents an order, a registration or the handling of a case; provide an option for manual entry or checking.
5. Usage limits
From 5 November 2026, use without a key is subject to a numerical quota: a reserve of 60 requests per IP address, which is refilled at two requests per second (about 120 requests per minute), and at most 3,000 requests per day; when an address list is checked (/clean), each row counts as one request. The exact numbers and the description of the 429 response are in the “Limits” section of the API documentation; tightening the quota is a material change (section 8.2). Until then, the service applies a brake against abuse: an IP address that sends more than ten requests per second receives a 429 response. If we issue an API key, we communicate the limits that apply to the key — for example, the number of requests that may be sent per minute — in the message about the issue of the key; tightening these later is a material change (section 8.2). And the following conditions apply to everyone:
- Do not load the service in a way that takes it away from others — keep the number of parallel requests and new connections moderate.
- The database may be used freely by querying it — for individual searches and item-by-item processing. However, copying out or bulk downloading the entire dataset is not permitted: the service is meant for querying, not for copying.
- Apart from the address, do not send any other personal data in the query: no name, email address, phone number, client or order ID, birth details or ID document number. These are not needed for cleaning addresses.
- Do not create the impression that adatka is an official register or that it is connected with a state body.
- Do not circumvent the technical restrictions.
If, in the query, you send an address or coordinates relating to another natural person — for example, your customer's delivery address — you are the controller with respect to those data, and we are the processor. The conditions for this are set out in the Data processing terms; they form part of these Terms of service.
If use hinders others, the operator may restrict or refuse access. This may also happen without prior warning if the operation of the service is at stake. The details are described in section 8.12.
6. The results and the source licences
The use of the API's results is governed jointly by these terms, any individual agreement, and the licences of the sources indicated for the result.
- KSH: the KSH's terms applying to the dataset used, and attribution;
- GeoNames: CC BY 4.0, with attribution;
- Magyar Posta Partner Extra: under the terms governing access and re-use. Part of the postal code and street data comes from Magyar Posta's published datasets. This layer has been made live (based on the dataset of 21 September 2026): if this layer also contributed to the match, Magyar Posta also appears in the response's list of sources;
- OpenStreetMap: ODbL 1.0, with the attribution “OpenStreetMap contributors” and under the terms of the licence.
The ODbL obligations also depend on whether the user creates and makes publicly available a produced work or a derivative database. Before creating or publishing a larger dataset, examine the original licence terms.
7. Liability
The service is available “as is”. The operator is not liable for damage resulting from missing, outdated or incorrect data, nor for damage resulting from an outage of the service. This is the price of the service being free of charge, and that is why section 4 exists.
This section does not limit the rights to which a consumer is entitled by law, nor does it limit the liability under the GDPR for the processing of personal data. Liability for data processing carried out on your behalf is governed by section 13 of the Data processing terms.
8. Amendment and termination
This section describes for what reasons and how these terms and the service may change, how far in advance and how we notify you, what you can do if you do not agree with the change, and what happens if the service or your access ends.
8.1. For what reasons we may amend the terms
We may amend the terms unilaterally only for one of the following reasons, and only in the manner described in section 8:
- a change in legislation, or a decision of a court or an authority;
- a change in the terms of use (licence) of a data source, or a data source no longer being usable (see section 6);
- protecting the security of the service, preventing abuse, or a change in the server or in the technical operation;
- a significant change in the load on the service or in its operating costs;
- the introduction of a new feature, endpoint or data source, or the redesign or discontinuation of a feature or data source;
- the end of the free-of-charge beta or the introduction of a paid plan (see sections 1 and 9);
- a change in the operator's legal status, or the transfer of the service to another operator (section 8.10);
- correcting errors in the text, or making the text more precise or easier to understand.
The service being temporarily unavailable because of maintenance or a fault (section 4) is not an amendment.
8.2. What counts as a material change
A material change is any amendment that affects any of the following — unless the amendment is solely in your favour (section 8.3):
- your rights and obligations: a new obligation, prohibition or condition (for example, a new limit on use or an attribution obligation), or the narrowing of any of your rights;
- fees and free-of-charge use: the introduction of a fee, another payment obligation or a paid plan, or a change in the conditions of free-of-charge use;
- the scope of the service: the discontinuation of a feature, an API endpoint, a field of the response or a data source, or a change as a result of which an integration that has worked correctly until then stops working unless it is modified;
- limits: the introduction or tightening of a numerical quota or of a limit on the frequency of queries, or making access conditional on an API key or another new condition;
- data processing: if we were to use your personal data for a new purpose, pass it on to a new recipient or processor, transfer it outside the European Economic Area or keep it for longer than before, or if we were to ask you for new data for continued use of the service (in that case, we also amend the Privacy notice in the same way, in advance);
- liability: further limitation or exclusion of our liability, or extension of your liability;
- applicable law and disputes: the governing law, the competent court, the method of or the deadline for resolving disputes (section 9);
- termination: the conditions for restricting access, for termination by notice and for discontinuing the service, or the deadlines undertaken in section 8;
- the identity of the contracting party: if another person takes over the service (section 8.10).
If it is doubtful whether a change is material, we treat it as material.
8.3. What is not a material change
- a linguistic, spelling or editorial correction that does not affect the content;
- a clarification that makes the text easier to understand but changes neither the service nor your rights and obligations — for example, updating a dataset date given in the text;
- a new feature, endpoint or field, if its use is not mandatory and it does not change the existing ones;
- a new data source, if it does not change the existing endpoints and fields and its licence does not impose a new obligation on you;
- an amendment of the Privacy notice that describes processing already under way more precisely or more completely, narrows the processing in your favour, or describes new processing that applies only to those who start using a new feature after publication (for example, who request an API key) — we publish such an amendment without delay;
- a change that is solely in your favour: for example, relaxing a limit, extending a deadline, a new right or a more favourable condition.
A change that is not material takes effect on the day of publication.
8.4. How and how far in advance we notify you
For a material change:
- we publish the amended text at least 30 days before it takes effect, with the date on which it takes effect and a short summary of the changes, and we indicate on this page where it can be read. Until it takes effect, the earlier text remains in force;
- we indicate the change at the top of the home page, from publication until the 30th day after it takes effect;
- on the day of publication, we send an email to those who have a valid API key at that time: to the address to which we sent the key, or which they later gave for contact purposes. For anyone to whom we issue a key between publication and the date on which the change takes effect, we indicate the change in the message about the issue of the key. In the message, we describe what changes, from when, and what you can do if you do not agree (section 8.6). This message is a service notice (Privacy notice, section 6.2): it is not a newsletter and contains no advertising.
For those who have no API key, we indicate the change on this page and on the home page.
For a change that is not material, we publish the amended text on this page with a short description of the change and the date on which it takes effect; we do not indicate it on the home page and do not send an email.
Every change — material and non-material alike — appears at the top of the page, in the line beginning with the words “In force:”: when, in which section and what changed. There, a material change is distinguished by the label “Material amendment”.
If we have concluded an individual agreement with you, amendments are governed by its provisions; where the individual agreement makes no provision, this section applies.
8.5. Urgent change
We may bring an amendment into effect at shorter notice, or if necessary with immediate effect, if
- legislation or a decision of a court or an authority requires it and does not allow for the 30-day period;
- the rightholder of a data source prohibits its use, or changes its terms at shorter notice;
- this is necessary to avert a danger directly threatening the service, the users or the data (for example, an attack, abusive mass querying, a personal data breach);
- we have to replace a processor because the hosting provider or the email provider suddenly drops out.
In such cases, too, we notify you in accordance with section 8.4, as soon as possible, and we state the reason for the urgency. If the urgent change is material, you have the rights described in section 8.6 in the same way.
8.6. If you do not agree with the change
- Until the change takes effect, the earlier terms apply to you.
- You may stop using the service at any time — both before and after the change takes effect — without giving reasons (section 8.11). This involves no fee, contractual penalty or other cost.
- If you have an API key, you can request its revocation (section 8.11).
- If in the future you use a paid service and you end the agreement because of a material change, we will refund the part of the fee paid in advance that relates to the remaining period after termination, no later than 14 days after we become aware of the termination.
8.7. What continued use means
If you continue to use the site or the API after the change takes effect, you thereby accept the amended terms. Not replying to our message, or not objecting to the amendment, does not in itself constitute acceptance.
However, continued use is not enough if the amendment
- establishes a fee or another payment obligation — free-of-charge access does not automatically turn into paid access;
- introduces a term that differs substantially from the law or from customary contractual practice; we inform you of such a term separately.
Such an amendment becomes part of the agreement only if you expressly accept it, for example in a reply message. Until you do so, such an amendment does not apply to you: you may use the free-of-charge service under the earlier terms until it ends under section 8.12 or 8.13.
8.8. No retroactive effect
An amendment applies only to use after it takes effect. Queries sent earlier and results received earlier are governed by the terms in force at the time of the query; you may continue to use these results after the amendment under the licence terms of section 6 as in force at that time.
8.9. Earlier versions
We identify each version by the date on which it takes effect, and we keep the earlier versions. If you need one of them, write to info@adatka.hu stating the date for which you want the text that was in force, and we will send it to you by email within 8 days. In these, too, we provide the operator's name and place of residence only in the manner described in section 9. You can save or print the text in force on this page at any time.
8.10. If the operator's legal status or identity changes
If the operator registers as a sole trader, the contracting party does not change: the same person continues to provide the service. We will publish the operator's details as described in section 9 and in the Legal notice, no later than the launch of the paid service.
If a company or another business takes over the service, the agreement, together with all its rights and obligations, passes to it only with your consent (transfer of contract, szerződésátruházás). We will notify you of the transfer at least 30 days in advance, in accordance with section 8.4; in the notice and in the Legal notice, we give the transferee's name, registered office, registration details and the date of the transfer. If you use the service on or after the date of the transfer, you thereby consent to the agreement continuing with the transferee; if you do not agree, you may stop using the service (section 8.11). The transfer does not in itself change the terms; if the transferee wishes to change them, it may do so only in accordance with section 8. At the same time as the notice, we also describe in the Privacy notice which personal data pass to the transferee with the transfer.
8.11. You can end the agreement at any time
You can end the agreement at any time, without giving reasons and free of charge: it is enough to stop using the service. If you have an API key and request its revocation, write to info@adatka.hu from the email address to which we sent the key; if you no longer have access to that address, write from another address, and we will check in another way that the key is yours. We fulfil the request without delay, within 8 days at the latest (for a request from another address, after the check), and confirm it by email. The service rejects requests that arrive with a revoked key.
8.12. If we restrict or terminate your access
- We may restrict or terminate your access immediately, without prior warning — in the case of an API key, by revoking the key — if the use seriously breaches section 5, or if it endangers the operation of the service, other users or the data.
- If the breach is less serious and we have your email address, we first warn you and give you a reasonable deadline to stop the non-compliant use.
- For other reasons — for example, if during the beta we can no longer maintain your key — we may revoke the API key with a notice period of at least 30 days.
- We state the reason for the restriction or revocation by email if we have your email address, unless the law prohibits this or disclosing the reason would endanger the security of the service. If you think we have made a mistake, write to info@adatka.hu: we will reply on the merits within 30 days, in accordance with section 9.
8.13. If we discontinue the service
We may discontinue the service in whole or in part (for example, an API endpoint). We give notice of this at least 30 days in advance on this page and on the home page, and we send an email to the recipients described in section 8.4. Until then, the service continues to operate under the beta conditions described in section 4.
We discontinue it at shorter notice or immediately only if
- continued operation is not possible or not lawful because of legislation or a decision of a court or an authority;
- the right to use an indispensable data source ceases;
- there is a security danger directly threatening the service that cannot be averted in any other way; or
- operation becomes impossible for another reason beyond our control.
In such cases, we inform you as soon as possible, in the manner described above.
8.14. What happens on termination
- The API keys affected by the termination cease to be valid; the service rejects requests that arrive with them.
- We keep the data relating to you — for example, the API key data, the usage data and the correspondence — for the period set out in the Privacy notice, and delete them afterwards; they are deleted from the backups as the backups are replaced.
- You may continue to use the results received before termination under the licence terms described in section 6.
- For use before termination, section 7 (liability), section 9 (applicable law and disputes) and section 8.9 (earlier versions) continue to apply after termination.
8.15. Have a fallback
The service runs as a free-of-charge beta (section 4), and it may end as described above. Therefore, do not build on it a process that does not work without it — have a fallback.
9. Applicable law and disputes
These terms and the agreement are governed by Hungarian law. If you are a consumer — that is, you use the service as a natural person, not for business or professional purposes — this choice of law does not deprive you of the mandatory protective rules that would apply to you in the absence of a choice of law; these may include the rules of the country where you live.
If you have a dispute with us, please first write to info@adatka.hu describing what happened, when, and what you are asking for; if you have them, attach the query and the response you received. We will examine it and reply on the merits by email within 30 days of receipt of your message; if we reject your request, we will give reasons.
adatka.hu is currently operated by a private individual — not as a sole trader and not through a company — as a free-of-charge beta (see sections 1 and 4). A paid service will only start once the operator has registered as a sole trader, or once the service is provided by a registered company. By then, we will publish in the Legal notice the name, registered office, registration number or company registration number, and tax number of the sole trader or of the company, and we will supplement this section with a postal address for submitting complaints, and with information about the conciliation boards (békéltető testület) and the consumer protection authority. If you are already entitled by law to turn to an authority or a conciliation board, this section does not limit that right.
Going to court does not require that you first try to settle the dispute with us. You can enforce your claim against us before the courts in Hungary; which court is competent is determined by Act CXXX of 2016 on the Code of Civil Procedure. As a general rule, the case is heard by the court for the place of residence or registered office of the defendant (the party being sued). A monetary claim of at most HUF 3 million that has fallen due must normally — if both parties have a known address in Hungary — be enforced by means of an order for payment (fizetési meghagyás), before a notary.
The statement of claim and the application for an order for payment must state the name of the other party (the defendant or the obligor, respectively) and at least their place of residence or registered office. We do not publish the operator's name and place of residence on the site, but we provide them:
- to the body conducting the proceedings, if a court, a notary, an authority or a conciliation board makes an official request to us;
- to you or anyone else who indicates, in a message written to info@adatka.hu, that they wish to enforce a legal claim against the operator and need these data for that purpose.
The request is complete if, in the message, you:
- give your own name and, if you act on behalf of someone else (for example, as a lawyer), also on whose behalf you act;
- briefly describe what claim you wish to enforce, and in what proceedings (for example, in a lawsuit, in order for payment proceedings, or in proceedings before an authority or a conciliation board);
- declare that you will use the data only for this purpose.
Before providing the data, we do not examine whether the claim is well founded; you do not need to attach any document or proof. Within 8 days of receipt of the complete request, we send the operator's name and place of residence by email to the address from which the request was sent. If something is missing from the message, we tell you what is missing within 8 days of its receipt. We keep the request and our reply for the period described in the Privacy notice.
You can check which district court (járásbíróság; in Budapest, kerületi bíróság) and which regional court (törvényszék) a settlement or postal code belongs to on the official website of the courts (birosag.hu), under the “Bíróság kereső” (court finder) menu item, together with their contact details.
This section does not limit the rights to which a consumer is entitled by law — including the right to sue before the court of their place of residence, and to be sued only there, if Hungarian or EU law guarantees this. Nor does it limit your right — whether or not you are a consumer — to bring proceedings concerning the processing of your personal data before the court described in section 5 of the Privacy notice, including, if you live in another Member State of the European Union, before a court there (Article 79(2) GDPR).