Contact

One person reads every message. We no longer publish an email address, because a public address only collects spam.

What I respond to

• Calculator bugs. If a number is wrong, please send the inputs you used and what you expected. I fix these fast because they affect anyone using the tool.
• Calculator requests. If a niche on this site is missing a calculator you'd actually use, tell me what it should solve and what inputs make sense. I build the ones with real demand first.
• Niche requests. 111 hobbies isn't comprehensive. If your hobby is missing and it has working math behind it, send the topic and a sketch of what tools/articles would help.
• Correction requests. If I got a fact wrong, please name the specific page and the correction with a source. I'd rather be right than feel right.
• Partnership inquiries. I don't take sponsored content. I don't write "best of" lists for manufacturers. I do consider affiliate program adds (beyond eBay) when they match the honest-math angle of the site.

What I don't respond to

• SEO/link-building outreach. The answer is no. Please don't follow up.
• Guest post pitches with AI-generated drafts. I can tell. Please don't.
• "Have you heard of [my unrelated product]?" cold pitches.

Response time

I read every message within a week. I respond to the ones above within two. If I don't respond, it's likely because it fell under "what I don't respond to" — please don't take it personally.

Mailing address

If you actually need a physical address for legal reasons, send a message first and I'll provide one. I don't post my home address on the open web for predictable reasons.