Last updated: October 10, 2026
1. Provider and agreement
These terms govern zengomaster.net, operated by VELDRION GROUP INC, 4450 ARAPAHOE AVE, BOULDER, CO 80303, United States. Contact support@zengomaster.net. By using the service you agree to these terms. You must be at least 16 to use the service; to purchase, you must be of legal contracting age or have a parent or guardian make the purchase.
2. What the service provides
zengomaster provides Go practice on 9 × 9, 13 × 13, and 19 × 19 boards, a beginner computer opponent, two-player play on the same device, six introductory lessons, a capture exercise, undo, optional local game saving, and SGF export. Remote matchmaking, cloud accounts, professional coaching, and professional-strength analysis are not included. Features are described on the membership page. Public tools can be used without beginning a paid trial.
3. Trial and annual subscription
The annual price is US$99.00 USD for the English checkout or ¥16,999 JPY for the Japanese checkout, including applicable taxes. A free trial lasts exactly 60 minutes from confirmed subscription enrollment. Unless canceled before it ends, the full annual fee is automatically charged to the authorized payment method. The subscription renews annually at the same disclosed price and currency until canceled. Each trial is available once per customer. The exact trial deadline, initial charge, and renewal must be confirmed at checkout. Browsing or playing alone never authorizes payment.
4. Consent and payment
A payment method is required only at the hosted checkout. Before confirming, you must expressly agree to the trial, automatic annual charge, and renewal terms. The statement descriptor is ZENGOMASTER; a card issuer may add its own prefix. We do not collect card credentials in the website. A language change does not alter an existing contract. Any proposed price change will be disclosed in advance and applied only as permitted by law and the consent obtained.
5. Cancellation and refunds
Cancel through Manage membership or email support@zengomaster.net. Requests are effective when received. Cancel before the trial deadline to avoid the first charge, or before renewal to stop the next. No cancellation fee applies. Annual payments are fully refundable on request within 30 calendar days of each charge, including renewals. A refund ends associated paid access and renewal. The refund and cancellation policies explain the process and form part of these terms.
6. Acceptable use and intellectual property
Use the service lawfully. Do not interfere with security, attack the site, misuse another person’s payment information, or distribute malicious code. Website design, branding, text, and code are protected as applicable. We grant a personal, nonexclusive right to use the service; this does not transfer ownership. Your exported game records remain yours to use. Do not upload or send material that violates another person’s rights.
7. Local records and availability
Local game storage can be removed by your browser or device. Export important records; we cannot recover local data that we never receive. We aim to keep the site usable but do not guarantee uninterrupted availability. Practice scores are board-position estimates, not official tournament adjudications. No rank improvement or competition outcome is promised.
8. Responsibility and disputes
To the extent permitted by law, the service is provided as available and we are not responsible for indirect or consequential losses. Nothing excludes liability that cannot legally be excluded, or limits mandatory consumer rights. These terms are governed by Colorado law, subject to the mandatory protections and forum rights of your residence. Contact support first to seek a practical resolution; no mandatory arbitration or class-action waiver is imposed by these terms.
9. Changes and contact
Material changes will be posted with an updated date, and changes affecting a paid subscription will be communicated before they take effect where required. Contact VELDRION GROUP INC using the address or email above. English and Japanese versions describe the same offer; mandatory local consumer protections prevail over conflicting wording.