Ask AI to check unknown numbers before you call anyone back
Tsugunori Katayama, a retired company executive in Japan born in 1953 who teaches smartphone and AI skills to older adults, got 16 calls from unknown numbers over two months. He asked ChatGPT to look up each one and sort them. It flagged about three out of four as nuisance calls or possible scams.
What they did
He used to ignore calls from numbers he didn't recognize, but he got curious. So he pulled only the unknown numbers from his call history, leaving out his contacts. He asked ChatGPT to look up what each one was, sort them into groups, and put the results in a spreadsheet.
How it went
ChatGPT listed 6 of the 16 as spam or nuisance calls, 5 as possible fake-bill scams, and 1 as an overseas "one-ring" scam, where calling back racks up costly charges. It said the other 4 were unknown and to be careful with them. His takeaway: don't answer unknown numbers and don't call them back right away. Someone with real business will leave a voicemail or a text. If something worries you, talk it over with family or a local advisor. His post is in Japanese.
Worth knowing
An AI check is only as good as what it can find. It needs web search turned on, it can mix up numbers, and a number with no complaints isn't proof the caller is safe. Scammers also fake caller ID to look like a real bank or agency. Never call back a number just to find out who it was. If a call claims to be from your bank, Medicare, or a government office, call the number on your card, statement, or the official website instead. Block nuisance numbers on your phone and report scams to the FTC at ReportFraud.ftc.gov (in the U.S.).
Try it yourself
Copy this into ChatGPT (or any AI assistant). Replace the parts in [brackets] with your own details.
Below are phone numbers from my call history that I don't recognize, with the date of each call. I've left out my contacts and any names. Search the web for public reports on each number and sort them into: likely spam or sales calls, possible scams (say what kind), probably legitimate, or unknown. Give one line of reasoning per number and say when you found no information. Don't tell me any number is safe to call back. Instead, tell me how to check through an official phone number I look up myself. [paste numbers and dates]
Source: 片山嗣規 (Tsugunori Katayama), note (Tsugunori Katayama's blog), Aug 2, 2025. Read the original →
First-hand account by the person who did it. Summarized in our own words. Spotted a mistake or want this removed? Tell us.