Denwa
Look up unknown callers instantly.
Identify sources and detect spam calls.
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. Our proprietary scoring system evaluates spam risk on a scale of 0 to 100 based on user reviews and report counts. A higher score indicates a greater likelihood of spam.
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).
Recent Reports / Reviews
Featured Articles
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How much compensation can you expect from suing a persistent nuisance caller? Benchmarks from past court decisions, litigation costs, cost-effectiveness, and alternative remedies explained.