compbook

Privacy Policy

Effective: September 28, 2026 / Revised: October 2, 2026

This is a translation for convenience. If it differs from the Japanese version, the Japanese version governs.

The operator of CompBook (the "Service") handles users' information as follows.

1. Information stored in your browser

  • The playbooks, comps, boards, notes and other data you create, and your display theme setting, are stored only in your browser (localStorage).
  • Except when you use a pickup code (item 4), this data is not sent to the operator's servers and the operator cannot view or access it. Clearing your browser data also deletes this information.

2. Information recorded when you visit

  • The Service is hosted on Vercel (Vercel Inc.). When you view a page, Vercel processes and records information such as your IP address, the location estimated from it, your browser type, the time of access and the pages you view.
  • The operator may review these records to the extent Vercel makes them available, and uses them to provide the Service, troubleshoot problems and prevent unauthorized access.
  • Vercel's own handling of this information is governed by Vercel's privacy policy (Vercel Privacy Notice).
  • To understand how many pages are viewed, we use the analytics tool Vercel Web Analytics. When you view a page, the page you viewed, the referrer, the country estimated from your IP address, and your browser, OS and device type are sent to Vercel. It uses no cookies, and it does not identify you across days or identify you personally. We use the aggregated results only to understand usage and improve the Service.

3. Information received through inquiries

  • The contact form receives the type of inquiry, your message and, optionally, a reply email address. We use them only to respond to that inquiry.
  • Submitted content is delivered to the operator's email account through the email delivery service Resend (Resend, Inc.). It is not stored on the Service's servers or database. Resend's handling is governed by Resend's privacy policy (Resend Privacy Policy).
  • To prevent mass submissions by bots, the form and pickup code issuance use Cloudflare Turnstile (Cloudflare, Inc.). When the form is shown, your browser connects to Cloudflare, which processes information such as your IP address and browser details. Cloudflare's handling is governed by Cloudflare's privacy policy (Cloudflare Privacy Policy).

4. Information kept for pickup codes

  • When you issue a pickup code with "Send / receive playbooks", the data of the playbooks you choose (comps, boards, notes and so on) is sent to the Service's server and kept in its database.
  • The data is used only to hand it to the device where the code is entered. It can no longer be read 24 hours after issue, and expired data is then deleted automatically during later server processing. The code itself is not stored; only a hash value used to look it up is kept.
  • Anyone who knows the code can read the data, so share the code only with the person you mean to.
  • The database uses a service provided by Supabase (Supabase, Inc.). Supabase's handling is governed by Supabase's privacy policy (Supabase Privacy Policy).

5. What we currently do not do

The Service currently does not do the following.

  • Account registration or login
  • Accepting your name, email address or similar input (except through the contact form)
  • Using advertising or tracking cookies

If we introduce any of these, we will revise this policy before doing so and announce it on this page.

6. Provision to third parties and outsourcing

  • Except where required by law, we do not provide personal information to third parties without the person's consent.
  • To the extent necessary to operate the Service, we may entrust the handling of information to the hosting provider (Vercel), the email delivery provider (Resend), the bot-check provider (Cloudflare) and the database provider (Supabase).
  • All of these providers are companies based in the United States, and information may be processed in the United States and other countries. The United States has no comprehensive federal law equivalent to Japan's Act on the Protection of Personal Information; instead, some states have their own laws, such as the California Consumer Privacy Act. Details of the U.S. system are available in the survey of foreign personal information protection systems by the Personal Information Protection Commission of Japan (in Japanese).
  • The operator has confirmed that each provider's terms, privacy policy and similar documents set out measures to protect personal information, such as not using it beyond the entrusted purpose and keeping it secure. On request, we will provide information about these measures.

7. Retrieval of game images

Images of champions, items and so on are fetched by the Service's server from Riot Games (Data Dragon) and CommunityDragon, converted, and then displayed. Your browser does not connect directly to those servers to display the images.

8. Security

Information received through inquiries is kept in an email account that only the operator can use, and is deleted within one year after the inquiry has been handled. Data kept for pickup codes is stored in a database that only the operator can connect to, and is deleted automatically as described in item 4.

9. Requests for disclosure and the like

If you wish to be informed of the purpose of use of, or to request disclosure, correction or suspension of use of, personal information about you held by the operator, please contact the address below. We will confirm your identity and respond as required by law.

10. Operator

CompBook is run by an individual operator. The operator's name and address will be provided without delay if you request them through the contact below.

11. Changes to this policy

We may change this policy as needed. Changes apply from the time they are posted on this page. We will announce important changes on this page in advance.

12. Contact

Please contact us through the contact form.