Terms of use of SuperMemo API

§ 1. Definitions and General Provisions

  1. Service Provider (SuperMemo) – SuperMemo World sp. z o.o., with its registered office at ul. Wesoła 3, 60-598 Poznań, Poland, entered into the register of entrepreneurs under KRS number 0000027598, NIP: PL7822216681.
  2. API – a digital communication method, based on strict rules and documentation, enabling the transmission of requests between the User’s Application and the Service Provider’s server in order to use learning optimization algorithms.
  3. API Key – a unique identifier generated within the User’s Account, used to authorize access to the Service.
  4. Service – the website api.supermemo.com, operated by SuperMemo, available at api.supermemo.com (hereinafter: the “Website”), together with associated API applications made available to Users under the terms set forth in these Terms of Use (hereinafter: the “Terms”).
  5. Subscription – recurring monthly service that is automatically renewed for successive billing periods unless canceled by the User.
  6. Account – a User account created during registration in the Service, intended for use by a single individual.
  7. User – a natural person, legal entity, or organizational unit using the Service as part of software development projects.
  8. User Application – software installed on the User’s server or device that communicates with the Service Provider’s API.


 § 2. Type and Scope of Services

  1. The Service consists of providing access to the SM-20 algorithm (and other available versions) via an API for calculating optimal review intervals in learning processes.
  2. Main functionalities include:
    • Processing data related to user interactions (reviews),
    • Calculating precise future review timings based on probabilistic modeling,
    • Managing projects and usage limits within the User panel.


 § 3. Technical Requirements for API Use

  1. Use of the API requires a device with Internet access and proper implementation of communication code on the User’s side, in accordance with the documentation available on the Website.
  2. Communication is carried out by sending properly formatted requests and receiving responses in the format defined in the documentation.
  3. The User is fully responsible for the correct configuration of their application and for securing the API Key against unauthorized access.


 § 4. Registration and Conclusion of Agreement

  1. Use of the API requires creating an Account and accepting these Terms.
  2. The agreement is concluded at the moment the Account is created and the Terms are accepted by the User.
  3. The User is required to provide accurate information during registration and update it if changes occur.


§ 5. Subscription Plans and Fees

  1. The Service Provider offers various access plans differing in request limits and scope of services. A list of plans, service scope, and limits is available on the Website.
  2. Access to paid plans may be provided in the form of a Subscription. 
  3. The User may cancel the Subscription at any time by selecting the “Cancel Subscription” option available in the User panel.  
  4. If the User cancels the Subscription, it remains active until the end of the current billing period in which the cancellation was made. No partial refunds are provided for unused time.
  5. Unless the User cancels the Subscription before the end of the current billing period, the Subscription will be automatically renewed for an additional monthly billing period under the same conditions.
  6. Users are automatically informed about Subscription renewals via email. 
  7. Fees for Subscriptions are charged in advance for the applicable billing period.
  8. In the event that the User exceeds the limits of their selected plan, the Subscription may be automatically upgraded to the nearest higher plan. The corresponding fee for the upgraded plan will be charged accordingly. 
  9. If the Service Provider is unable to successfully charge the payment method associated with the User’s Account, the Service Provider reserves the right to suspend or cancel the subscription until the payment is successfully completed.
  10. The Service Provider may use third-party payment processors.


§ 6. User Rights and Obligations

  1. The User has the right to manage their Account, generate API keys, and report technical issues.
  2. The following are prohibited:
    • Sharing API Keys with third parties without the Service Provider’s consent,
    • Undertaking actions that disrupt the operation of API servers,
    • Reproducing, modifying, or decompiling algorithms provided by SuperMemo.


§ 7. Liability of the Service Provider

  1. The Service Provider makes reasonable efforts to ensure continuous availability of the API but does not guarantee uninterrupted operation due to maintenance or external factors.
  2. The Service Provider shall not be liable for damages resulting from incorrect API implementation by the User or failures of the User’s equipment.


§ 8. Complaints

  1. Complaints regarding API operation should be submitted to support@supermemo.com or via the contact form.
  2. The complaint should include a description of the issue, the time of occurrence, and identifying details of the key/account.
  3. Complaints will be reviewed within 14 days from receipt.


§ 9. Termination of Agreement

  1. The User may terminate the agreement at any time by deleting their Account.
  2. The Service Provider has the right to suspend access to the API in case of violation of these Terms, non-payment, or actions harmful to the Service.


§ 10. Final Provisions

Privacy and personal data protection are governed by a separate Privacy Policy.

Matters not regulated herein shall be governed by Polish law.

The Service Provider reserves the right to amend these Terms, with prior notification to Users via electronic means.

Last updated: 20 April 2026