Terms of Service

By accessing or using the QubitLang platform at qubitlang.net (the “Service”), including our quantum programming environment, cloud simulators, and hardware backend access, you agree to be bound by these Terms of Service. If you do not agree, you may not use the Service.

You must be at least 13 years old to use QubitLang. If you are under 18, you must have permission from a parent or legal guardian.

To access most features of QubitLang, you must create an account using a valid email address and password, or authenticate via a supported third-party provider such as GitHub. You are responsible for maintaining the confidentiality of your credentials and for all activity that occurs under your account.

You agree to provide accurate and up-to-date information during registration and to notify us promptly of any unauthorised access to your account.

QubitLang offers multiple subscription tiers: Developer (free), Starter (£25/month), Growth (£100/month), and Scale (£500/month). Each tier includes specific allocations for simulator hours, storage, and project limits as described on our Pricing page.

Paid plans are billed in British Pounds (GBP) on a monthly or annual basis. Annual plans are billed upfront at a discounted rate as displayed on our Pricing page. You authorise us to charge your chosen payment method on a recurring basis. You may cancel or change your plan at any time; changes take effect at the start of the next billing cycle.

We may offer a free trial of certain paid plans (e.g., a 14-day trial of the Growth plan). At the end of the trial period, your account will revert to the Developer (free) tier unless you subscribe to a paid plan. No payment information is required to start a free trial.

Certain subscription tiers include compute credits that can be used to submit jobs to third-party quantum hardware backends, including IBM Quantum (Eagle, Heron), IonQ (Aria, Forte), and Rigetti (Ankaa). Credits are consumed on a per-use basis according to the rates published on our Pricing page.

Access to quantum hardware is subject to availability and the terms of the respective hardware providers. QubitLang does not guarantee specific hardware uptime, queue times, or result accuracy. Quantum computation results are inherently probabilistic and may vary between runs.

Compute credits included with your subscription plan expire at the end of each billing cycle and do not roll over. Any additional compute credits purchased separately do not expire and roll over indefinitely.

You agree not to:

• Use the Service for any unlawful purpose or to violate any applicable laws or regulations.
• Attempt to gain unauthorised access to any part of the Service, other users' accounts, or connected quantum hardware systems.
• Submit malicious code, excessively large jobs, or workloads designed to disrupt or abuse simulator or hardware resources.
• Resell, redistribute, or sublicense access to QubitLang or its quantum backends without our prior written consent.
• Use automated tools to scrape, mine, or excessively burden the Service beyond normal usage patterns.
• Circumvent usage limits, rate limits, or billing mechanisms associated with your subscription tier.

We reserve the right to suspend or terminate accounts that violate these terms or that engage in abusive usage patterns.

Your content: You retain full ownership of all quantum programs, circuits, algorithms, and other content you create using QubitLang. We claim no intellectual property rights over your code or computation results.

Our platform: The QubitLang platform, including its programming language, compiler, IDE, circuit visualisation tools, AI-powered optimisation features, documentation, and website design, are the intellectual property of QubitLang and are protected by applicable copyright and intellectual property laws.

If you create or join a team or organisation account, the account owner is responsible for managing member access and roles (owner, admin, member, viewer). The account owner assumes responsibility for all activity conducted by team members under the organisation.

Team members must individually agree to these Terms of Service. Removing a member from an organisation does not delete their personal QubitLang account.

QubitLang integrates with third-party services to provide its functionality, including but not limited to quantum hardware providers (IBM, IonQ, Rigetti), authentication services, and payment processors. Your use of these third-party services is subject to their respective terms and privacy policies.

QubitLang is not responsible for the availability, accuracy, or performance of third-party services.

We strive to maintain high availability of the Service but do not guarantee uninterrupted access. We may perform maintenance, updates, or modifications to the Service at any time. For Scale-tier customers with SLA guarantees, specific uptime commitments are detailed in your service agreement.

We reserve the right to modify, suspend, or discontinue any feature of the Service with reasonable notice.

Monthly subscriptions are non-refundable. If you cancel a monthly plan, you will retain access to paid features until the end of your current billing cycle, after which your account will revert to the Developer (free) tier.

Annual subscriptions may be eligible for a pro-rata refund if you cancel within the first 30 days of your annual billing period. After 30 days, no refund will be issued and you will retain access until the end of the annual period. To request a refund, contact us at support@qubitlang.net.

Compute credits, whether included with your plan or purchased separately, are non-refundable once used. Unused purchased credits remain in your account and may be refunded upon request if your account is in good standing.

The Service is provided on an “as is” and “as available” basis, without warranties of any kind, whether express, implied, or statutory. To the maximum extent permitted by applicable law, QubitLang disclaims all warranties, including but not limited to implied warranties of merchantability, fitness for a particular purpose, non-infringement, and accuracy of results.

Without limiting the foregoing, QubitLang does not warrant that the Service will be uninterrupted, error-free, or secure, that defects will be corrected, or that quantum computation results will be accurate or suitable for any particular scientific, commercial, or operational purpose.

You may close your account at any time by contacting us or through your account settings. Upon termination, your access to the Service will cease and your data will be handled in accordance with our Privacy Policy.

We may suspend or terminate your account if you violate these Terms, engage in abusive behaviour, or fail to pay applicable fees. We will make reasonable efforts to notify you before termination except in cases of severe violations.

To the maximum extent permitted by law, QubitLang and its team shall not be liable for any indirect, incidental, special, consequential, or punitive damages arising from your use of the Service, including but not limited to loss of data, loss of profits, or damages resulting from inaccurate quantum computation results.

Quantum computation results are approximate by nature due to noise, decoherence, and hardware limitations. QubitLang makes no warranty that results from quantum backends will be accurate, reproducible, or suitable for any particular purpose.

Our total liability to you for any claims arising under these Terms shall not exceed the amount you have paid to QubitLang in the 3 months preceding the claim.

These Terms shall be governed by and construed in accordance with the laws of England and Wales. Any disputes arising under these Terms shall be subject to the exclusive jurisdiction of the courts of England and Wales.

We may update these Terms from time to time. When we make material changes, we will notify you via email or a prominent notice on the Service. Your continued use of QubitLang after such changes constitutes acceptance of the updated Terms.

If you have questions about these Terms of Service, please contact us at support@qubitlang.net.