1. About These Terms

These Terms & Conditions (“Terms”) govern your access to and use of the LEDLITY website, the LEDLITY Toroidal Inductor Calculator, user accounts, engineering calculation services, projects, reports, and related features (collectively, the “Service”).

The Service is operated by:

In these Terms, “ESTA”, “LEDLITY”, “we”, “us”, and “our” refer to ESTA PR Uroš Nešić as the operator and provider of the LEDLITY Service. “You” and “user” refer to the person or organization accessing or using the Service.

By creating an account, accessing the Service, or using the LEDLITY Toroidal Inductor Calculator, you agree to these Terms. If you use the Service on behalf of a company or other organization, you represent that you have authority to accept these Terms on its behalf.

2. The LEDLITY Service

LEDLITY provides engineering software intended to assist with the design and evaluation of toroidal inductors.

Depending on the available features, the Service may include:

• toroidal core and wire selection;
• turn-count calculations;
• inductance calculations;
• DC-bias analysis and inductance-retention evaluation;
• magnetic and flux-related calculations;
• winding-feasibility checks;
• copper-loss and core-loss calculations;
• thermal estimation;
• evaluation of alternative design candidates;
• saved engineering projects;
• calculation results and reports; and
• other engineering tools and features that may be introduced over time.

The availability, scope, and implementation of individual features may change as the Service is developed and updated.

3. Engineering Use and Responsibility

LEDLITY is an engineering assistance tool. Calculation results are based on user inputs, implemented engineering models, available material and component data, and the applicable validity ranges of those models and data.

Results produced by the Service do not constitute certification or a guarantee that a physical component or final product will achieve a particular level of performance, safety, reliability, manufacturability, or regulatory compliance.

You are responsible for reviewing your input data and calculation results and for determining whether a proposed design is suitable for your intended application.

Designs intended for practical use should be subjected to appropriate engineering review, prototyping, measurement, testing, validation, and safety assessment before being used in production or in a final product.

Additional information about the engineering scope and limitations of the Service is provided in our Disclaimer, which forms an important part of the conditions under which the Service is offered.

4. User Accounts

Certain features of LEDLITY require a registered user account.

You agree to provide accurate information when creating and maintaining your account and to keep your login credentials confidential.

You are responsible for activity carried out through your account unless the activity results from circumstances for which we are legally responsible.

You should notify us promptly at office@esta.rs if you believe that your account has been accessed without authorization.

User accounts are intended for use by the registered user or the organization for which the account was created. You may not sell, transfer, rent, or otherwise commercially redistribute access to your LEDLITY account or calculation balance without our written permission.

5. Free Calculations

New eligible accounts may receive a limited number of complimentary engineering calculations. At present, the standard introductory allowance is three (3) free calculations per eligible account.

Free calculations are provided to allow users to evaluate the Service. They have no cash value, cannot be exchanged for money, and cannot be transferred between accounts.

We may also provide additional complimentary or promotional calculations during early-access programs, testing periods, promotions, or other campaigns.

We may change or discontinue free or promotional calculation allowances for future users or future promotions. Any change will not convert previously purchased calculations into promotional calculations.

Attempts to create multiple accounts primarily for the purpose of repeatedly obtaining free calculation allowances may result in restriction or suspension of access.

6. Calculation Packages

Users may purchase prepaid calculation packages that add a specified number of engineering calculations to their LEDLITY account.

Available packages, prices, currencies, and promotional offers are shown on the website or during checkout before a purchase is completed.

Unless explicitly stated otherwise, calculation packages are one-time purchases and are not subscriptions. Purchasing a package does not create an automatically renewing payment obligation.

Purchased calculations:

• are associated with the applicable LEDLITY account;
• may be used only within the LEDLITY Service;
• have no cash or monetary value outside the Service;
• cannot be redeemed for cash;
• cannot normally be transferred between user accounts; and
• may not be resold or commercially redistributed.

Each successfully completed engineering calculation may reduce the available calculation balance according to the rules displayed within the Service.

7. Orders, Payments, and Paddle

Paid calculation packages are processed through Paddle, our authorized online reseller and Merchant of Record.

Our order process is conducted by our online reseller Paddle.com. Paddle.com is the Merchant of Record for all our orders. Paddle provides all customer service inquiries and handles returns.

When you make a purchase through Paddle, the purchase transaction, payment processing, applicable transaction taxes, payment confirmation, and order-related matters are handled by Paddle under the terms presented during checkout.

LEDLITY remains responsible for providing access to and supporting the engineering Service itself, subject to these Terms.

Prices and applicable taxes are displayed before you confirm a purchase. The currency presented at checkout may depend on your location and the payment options available through Paddle.

Paddle may issue the applicable receipt or invoice for your transaction.

8. Delivery of Purchased Calculations

Purchased calculations are digital service entitlements and no physical product is shipped.

Following confirmation of a successful transaction, the purchased calculation allowance is normally added automatically to the associated LEDLITY account.

Fulfilment may depend on successful communication between Paddle and the LEDLITY system. If payment has been successfully completed but the purchased calculations do not appear in your account within a reasonable time, please contact us at office@esta.rs.

We may use transaction identifiers and related order information to verify a purchase and prevent duplicate fulfilment.

9. Refunds

We offer a 30-day money-back guarantee for eligible purchases, subject to the conditions described in our Return and Refund Policy and to any mandatory rights available under applicable law.

Refunds for transactions processed by Paddle are handled through Paddle. Users should not expect a refund to be paid directly by ESTA outside the Paddle transaction process.

Where a refund is granted, unused purchased calculations associated with the refunded transaction may be removed from the user’s LEDLITY account. The treatment of partially used calculation packages is described in our Return and Refund Policy.

10. Acceptable Use

You agree to use LEDLITY lawfully and in a manner that does not interfere with the operation, security, integrity, or availability of the Service.

You must not:

• attempt to gain unauthorized access to the Service, other user accounts, servers, databases, or administrative systems;
• bypass or attempt to bypass calculation limits, payment controls, authentication mechanisms, or security measures;
• use automated systems to abuse, overload, scrape, or systematically extract data from the Service without our permission;
• attempt to manipulate calculation balances, transaction records, or account entitlements;
• introduce malicious code or intentionally interfere with the Service;
• use the Service in violation of applicable law or the rights of another person or organization; or
• reproduce, resell, sublicense, or provide unauthorized commercial access to the Service itself.

11. User Projects and Engineering Data

LEDLITY may allow you to save engineering projects, input parameters, calculation results, and related information within your account.

You retain your rights in engineering information and project content that you lawfully provide to the Service.

You grant us the limited rights necessary to store, process, calculate, display, back up, and otherwise technically handle that information for the purpose of operating, securing, maintaining, and providing the Service to you.

You are responsible for ensuring that information you upload or enter into LEDLITY does not unlawfully infringe third-party rights or violate obligations of confidentiality applicable to you.

Details about our handling of personal data are provided in our Privacy Policy.

12. Intellectual Property

The LEDLITY Service, including its software, calculation implementation, interface, website content, graphics, documentation, database structure, reports, branding, and other original materials, is owned by or licensed to ESTA PR Uroš Nešić and is protected by applicable intellectual property laws.

Subject to these Terms, we grant you a limited, non-exclusive, non-transferable right to access and use the Service for your own legitimate personal, educational, or professional engineering purposes.

This right does not transfer ownership of the Service, software, databases, calculation methods, source code, or other intellectual property to you.

You may use your own calculation results and engineering designs in your projects, documentation, prototypes, and commercial products, subject to any third-party rights applicable to data or materials used in those projects.

13. Manufacturer Data and Third-Party Rights

LEDLITY may contain technical data, product identifiers, manufacturer names, trademarks, part numbers, and information derived from published technical documentation.

Third-party trademarks, product names, and manufacturer identifiers remain the property of their respective owners.

Unless expressly stated otherwise, inclusion of manufacturer or product information in LEDLITY does not imply sponsorship, endorsement, certification, partnership, or approval by that manufacturer.

Users should verify critical technical parameters against current official manufacturer documentation before committing a design to production.

14. Service Availability and Updates

We aim to maintain reliable access to LEDLITY, but we do not guarantee that the Service will be available without interruption at all times.

Temporary interruptions may occur because of maintenance, software updates, hosting or network issues, security measures, third-party services, or circumstances outside our reasonable control.

We may update calculation methods, engineering datasets, validation rules, supported manufacturers or materials, interfaces, reports, and other features as the Service develops.

Such updates may cause results generated at different times to differ where models, data, or validation rules have legitimately changed. Accordingly, important engineering results should be retained together with appropriate project records and independently verified when required.

15. Suspension and Termination

We may restrict or suspend access to an account where reasonably necessary to protect the Service, other users, our legal rights, or system security, including where we reasonably believe there has been fraud, unauthorized access, abuse, manipulation of calculation entitlements, or a material violation of these Terms.

Where reasonably possible and appropriate, we will attempt to provide notice or an opportunity to resolve the issue.

Suspension or termination does not affect rights that cannot lawfully be excluded, including any applicable consumer rights or valid refund rights.

16. Disclaimer of Warranties

To the extent permitted by applicable law, the Service is provided on an “as available” basis. Engineering calculations and estimates depend on user inputs, available data, implemented models, and their respective limitations.

We do not warrant that a calculated design will satisfy every requirement of a particular physical application or that calculation results alone are sufficient to establish product safety, certification, regulatory compliance, or production readiness.

Nothing in these Terms excludes warranties, guarantees, remedies, or other rights that cannot lawfully be excluded under applicable consumer or other mandatory law.

17. Limitation of Liability

To the maximum extent permitted by applicable law, ESTA PR Uroš Nešić will not be liable for indirect, incidental, special, or consequential losses arising solely from reliance on an engineering calculation without appropriate professional review, testing, or validation.

Users remain responsible for the engineering decisions they make using information produced by the Service and for evaluating the suitability of a design for its intended physical application.

Nothing in these Terms is intended to exclude or limit liability where such exclusion or limitation is prohibited by applicable law, including liability that cannot legally be limited in relation to consumers.

18. Changes to These Terms

We may update these Terms when reasonably necessary to reflect changes to the Service, applicable law, payment arrangements, security requirements, or our business operations.

The current version will be published on this page with the applicable “Last updated” date.

Where a change materially affects existing users’ rights or obligations, we will provide additional notice where required by applicable law.

19. Governing Law and Mandatory Consumer Rights

These Terms, insofar as they govern the relationship between you and ESTA PR Uroš Nešić regarding use of the LEDLITY Service, are governed by the laws of the Republic of Serbia, without prejudice to any mandatory consumer protection rights that may apply to you under the law of your country of residence.

Your purchase transaction with Paddle is also subject to the terms presented by Paddle for that transaction, including any applicable country-specific provisions.

Nothing in these Terms is intended to deprive a consumer of protections that cannot lawfully be waived by contract.

20. Contact and Support

For questions concerning the LEDLITY Service, engineering functionality, your LEDLITY account, or these Terms, contact:

For payment, transaction, invoice, or Paddle order-support matters, customers may also use Paddle’s buyer support services.