Denwa
Find out who is behind unknown Japanese numbers - free.
Spam risk scores and user reviews for 090, 0120 and more.
How to Use
- 1
Enter a Number
Type the phone number you received a call from. Hyphens are optional.
- 2
Check Results
View caller information, spam score, and user reviews.
- 3
Share a Review
Post your experience as a review to help other users.
FAQ
How can I look up an unknown phone number?
Simply enter the number on Denwa to instantly check the caller's business name, region, and line type. An automatic caller identification feature is also available.
Can I check if a call is spam?
Yes. Each number is rated based on user reviews and shown with labels ranging from Safe to Danger. The more spam reports a number has, the closer its label is to Danger.
Can I post a review for a phone number?
Yes. You can post a review from the search results page. Share information using categories such as telemarketing, scam, or one-ring calls, along with a 5-level rating.
What types of phone numbers are supported?
We support major Japanese phone numbers including landlines (03, 06, etc.), mobile phones (070, 080, 090), IP phones (050), toll-free numbers (0120), and free-call numbers (0800).
Popular Articles
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Scam PreventionWhy Phone Scams Thrive in Japan - Structural Factors in International Perspective
Japan loses roughly 71.9 billion yen annually to phone fraud (2024). This article analyzes the structural factors - an aging society, cash-based economy, and trust in landlines - through international comparison.
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Impersonation scammers almost universally speak standard Japanese. Learn why they avoid dialect, the voice manipulation techniques they use, and how to spot fakes by listening carefully.
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Learn how one-ring scams work and the risks of calling back. Discover practical steps to avoid costly charges and where to seek help if you fall victim.
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Someone calls asking for a person you don't know. Learn how to handle wrong number calls and spot scams disguised as wrong numbers.
Key Terms
Frequently Reported Numbers
Phone numbers that have received user reviews and reports. Open a number's page to see the details.