Privacy policy

Last updated October 21, 2026

This policy explains what characterchart (characterchart.com, "we") collects, why, and who else handles it. characterchart is run by TOMI, an independent developer in Japan. Questions: contact@soukanzu.jp.

The short version

• You can make charts without an account. Those charts stay in your browser and are not sent to us.
• If you sign in, we store your email address and the charts you save so you can open them on any device.
• Payments go through Stripe. We never see or store your full card number.
• We use Google Analytics to understand how the site is used. We don't sell personal information and we don't show ads.

What we collect

Charts made without an account

Saved in your browser's local storage on your device. We don't receive them. Clearing your browser data deletes them, so download a backup if you need one.

Account details

When you sign in we store your email address. If you use Google sign-in, we also receive the name and profile picture on your Google account. Our sign-in system keeps session records, including the IP address and browser type a session was created from, so we can keep you signed in and protect your account.

Charts saved to your account

Chart titles and everything inside them: names, roles, notes, relationship labels, layout, and any photos you add. These are stored in our database so you can open and edit them anywhere.

Share links

When you share a chart, anyone with the link can view it, and we create a preview image of it for link previews. Stopping sharing or deleting the chart removes the link and the preview image.

Purchases

Stripe handles checkout and stores your payment details. We keep your Stripe customer ID and what you bought: plan, billing cycle, subscription status and renewal date, and which charts have a single-chart export.

Usage data

Google Analytics records pages viewed and editor events such as starting a chart, exporting or starting checkout, along with device, browser and approximate location. Our hosting provider also processes standard request data, such as IP addresses, to deliver and protect the site.

How we use it

• To run the editor, save and sync your charts, and show shared charts.
• To send sign-in links and messages about your account or purchases.
• To process payments and give you the features you paid for.
• To answer your questions and fix problems.
• To understand, in aggregate, which features are used, so we can improve them.
• To keep the service secure and prevent abuse.

Who else handles it

We use these service providers. Each processes data only to provide its service to us:

• Cloudflare: hosting, our database, share preview images, and security.
• Google: Google sign-in (if you choose it) and Google Analytics.
• Stripe: payments, subscriptions, and the billing portal.
• Brevo: sending sign-in emails.

We may also disclose information if the law requires it, or to protect the rights and safety of our users or the service. These providers may process data in the United States and other countries.

Cookies and local storage

• A sign-in cookie keeps you signed in.
• Local storage holds charts made without an account and editor preferences, such as Simple or Advanced mode.
• Google Analytics sets its own cookies.

You can block or delete these in your browser settings. If you do, signing in and saving in the browser may stop working. To opt out of Google Analytics, use Google's opt-out add-on.

How long we keep it

• Account details and saved charts: until you delete them or close your account.
• A chart you delete is removed from our database.
• Records of purchases: for as long as tax and accounting rules require.
• Sign-in sessions: they expire on their own.

Your choices

You can delete any saved chart in the editor at any time. To get a copy of your data, correct it, or delete your account and everything in it, email contact@soukanzu.jp from the address you sign in with. We'll reply within 30 days. Cancel a subscription any time from Manage billing in the account menu.

Children

characterchart isn't directed at children under 13, and we don't knowingly collect their personal information. If you think a child has given us personal information, contact us and we'll delete it.

Changes

If we change this policy, we'll update the date at the top. If a change is significant, we'll also say so on the site or by email.