Affiliate Disclosure

Period Tools participates in several affiliate programmes. That means a few of the outbound links on this site are affiliate links: if you click one and then sign up for a service or buy a product, we may receive a small commission at no extra cost to you.

Programmes we participate in

• Amazon Associates. When you click one of our Amazon links and make a qualifying purchase, we earn a small referral commission. As an Amazon Associate, we earn from qualifying purchases.
• Femtech and cycle-tracking apps. We may link to apps such as Flo, Clue, Natural Cycles, or Ovia. If we do, those links may be affiliated.
• Other relevant partners. Where a product or service genuinely fits the page topic, we may include affiliate links to that partner.

What we will not do

• We won’t let an affiliate dictate our content. What we write is independent of who pays us. If a partner asks us to remove a critical statement, we say no and pull the partnership instead.
• We won’t promote anything we wouldn’t use. If we link to a product or app, it’s because we genuinely think it’s useful — not because the commission is high.
• We won’t hide the disclosure. Every affiliated page links here from the footer.

Why affiliates fund the site

Period Tools is free to use and free of signup walls. Ads and affiliate commissions are how we pay for hosting, domain renewal, and the time we spend keeping the calculators accurate and the content up to date. Without them, this site wouldn’t exist.

Questions

If you have any question about a specific affiliate link or partnership, email us at [email protected].