Permissions guidance

Unless otherwise stated, all material on Numbermatics.com is copyright. Many websites republish material from other places. We don't. We research and write every single word ourselves. (Copyright notice.) Facts are in the public domain, but the way those facts are presented is not. If you wish to re-use anything, you will need our permission.

Permissions

As a general rule, we are happy for you to quote small snippets from the Numbermatics website provided you follow the rules below.

I want to use a small extract for a school project

Students! Want to use material from Numbermatics in your homework, essay or project? The answer is YES. There are two rules: You can only directly quote a maximum of 150 words per essay. Second, you must acknowledge numbermatics.com as the source.

That's all. If you follow those rules, there is no need to ask us for permission. If you need more than 150 words, please see below. Don't forget, you are free to rewrite, edit or summarize the information instead of directly quoting it.

We have added citation and link information to each entry, so it is easy to use Numbermatics as a reference.

I want to use a small extract on my blog or website

That's fine provided the extract is less than 150 words and you give us link to numbermatics.com.

If you follow those rules, there is no need to ask us for permission. If you need more than 150 words, please see below. You are welcome to edit, precis or summarize the information instead of directly quoting it. But in all cases you must link back to the Numbermatics page you lifted the text from.

We have added permalinks to each entry to make linking to the appropriate page as easy as possible.

People sometimes paste entire articles from encyclopedic sites such as Numbermatics into a forum or a wiki without mentioning where it came from. While we are delighted that people want to share our work, this is technically a violation of our copyright. (And also extremely bad manners.) It is much better for everyone if you post a short extract and link back to the rest of the article at Numbermatics.

I want to use a small extract in a book or print article

That's fine, provided the extract is less than 150 words and you mention www.Numbermatics.com as the source. No need to ask permission. For longer extracts see below.

It's not obligatory, but if you wish to tell us about your book or article we would certainly appreciate it. In many cases we can help to spread the word about your publication so it's worth letting us know.

Reproduction requests

Copyright notwithstanding, you may quote small (under 150 words) extracts for your own non-commercial projects provided you give us credit. Citations must include a link to www.numbermatics.com. This applies to essays, articles, books, websites and homework. We have helpfully added a citation box to all articles to make this easy for you.

If you wish to reproduce a substantial amount of our work (over 200 words), or if you wish to reproduce images, contact us for advice. We will be happy to help you.

Last updated 10 May 2015