Add a Conception Date Calculator to Your Website

Build Your Conception Date Calculator

Add this conception & reverse due date calculator to your website without building, hosting, or maintaining it yourself. The same embed works on WordPress, Wix, Squarespace, Webflow, and any HTML website.

This free tool is provided by Pregnancy Safe, which helps expecting parents track their pregnancy and check the safety of thousands of products and categories.

Choose an accent color, preview the calculator, and copy the embed code.

Conception & Reverse Due Date Calculator for WordPress

1. Edit the page where you want the calculator.
2. Add a Custom HTML block by searching for HTML or typing /html.
3. Paste the complete embed code, preview the page, and publish.

WordPress may remove iframes for users without permission to publish unfiltered HTML. If the calculator disappears after saving, ask a site administrator to add the block. Elementor or Divi users can paste the same snippet into the builder's HTML/code module. See the official Custom HTML block guide.

Conception & Reverse Due Date Calculator for Wix

1. In the Wix Editor, choose Add Elements → Embed Code → Embed HTML.
2. Select Enter Code, paste the complete snippet, and click Apply.
3. Stretch the Wix embed element to the full column width and at least 480px high.

Wix only displays HTTPS embeds and does not automatically make its embed container responsive. See Wix's official widget embed guide.

Conception & Reverse Due Date Calculator for Squarespace

1. Edit the page and add a Code block where the calculator should appear.
2. Choose HTML, paste the complete snippet, and save the page.
3. Check the published page on mobile and desktop.

Squarespace supports iframe code in advanced Code blocks on eligible paid plans. If it does not appear while you are logged in, check the public page in a private window. See Squarespace's official custom-code guide.

Conception & Reverse Due Date Calculator for Webflow

1. Add a Code Embed element to the page.
2. Paste the complete snippet, then save and close the code editor.
3. Publish the site and verify the calculator at narrow and wide widths.

A suitable Workspace or active Site plan is required for Code Embed. See Webflow's official Code Embed guide.

Conception & Reverse Due Date Calculator HTML and iframe code

Paste the complete snippet into your page's HTML where the calculator should appear. Keep the iframe at width="100%" and the height generated by the builder. If your site uses a Content Security Policy, allow frames from https://pregnancysafeapp.com.

How the Conception Date Estimate Works

From a known due date, the calculator counts back 266 days for estimated fertilization and 280 days for the estimated first day of the last period. From a last menstrual period, it estimates fertilization 14 days later and the due date 280 days later. The last-period mode therefore carries the same regular 28-day-cycle assumption as conventional LMP dating.

The familiar search term “conception date” is retained for findability, but ACOG notes that conception is an imprecise lay term. In this widget, the output specifically means estimated fertilization date. It cannot identify when intercourse or implantation occurred and cannot establish paternity. The surrounding six-day window reflects the ASRM fertile-window definition, but actual ovulation and fertilization timing varies.

Clinical and technical references:

• ACOG — Methods for Estimating the Due Date
• ACOG reVITALize — Gynecology Data Definitions
• ASRM — Optimizing Natural Fertility

Common Installation Questions