CONTACT
Contact
Report a bug, suggest a calculator, or send feedback about the site.
Contact form
Please use our Google Form. The form is currently labeled in Japanese, but messages in English are welcome. Add an email address only if you would like a reply.
The form opens in a new tab.
Reporting a problem
Please include the page URL, what happened, the inputs you used, the result you expected, and your device and browser. These details make the issue easier to reproduce.
How to fill in the Japanese form
You can write your message in English. Use this guide for the labels in the form:
- お問い合わせの種類 — Inquiry type (required). Choose 不具合の報告 for a bug report, ツールの要望 for a tool request, 表示・文章について for a display or wording issue, or その他 for other feedback.
- 対象ページのURL — Page URL (optional). Paste the address of the page your message is about.
- お問い合わせ内容 — Message (required). Describe your question or feedback here.
- 返信用メールアドレス — Reply email (optional). Fill this in if you would like a reply.
- プライバシーポリシーを確認したことへの同意 — Privacy acknowledgment (required). Read our Privacy Policy in English, then check 同意 to acknowledge that you have reviewed it.
Press 送信 — Submit when you are ready to send your message. フォームをクリア — Clear form removes the entries from the form.
Information not to send
Do not submit passwords, credit card details, home addresses, confidential information, or other personal information that is not needed to handle your message.
How form submissions are handled
Your message is sent to the site operator through Google Forms. See our Privacy Policy for details.