The quick way people calculate a sibling age gap is subtracting one birth year from another. It’s usually close, but it’s often wrong by close to a year, and the reason is simple once you see it.<\/p>\n
Say one sibling was born in December 2015 and the other in January 2018. Subtract the years: 2018 minus 2015 is 3. But count the actual months between December 2015 and January 2018, and it’s only 2 years and 1 month, not 3. The birth month and day matter just as much as the year, and ignoring them can throw the answer off by nearly a full year in either direction depending on which sibling was born earlier in the year.<\/p>\n
The accurate way is to subtract full dates, not just years: take the exact birth date of each sibling and count the years, months, and days between them the same way you’d count anyone’s age.<\/p>\n
There’s no official standard here, but a common informal way people group sibling age gaps is:<\/p>\n
These aren’t scientific categories, just a common-sense way people talk about it. A 13-month gap and a 23-month gap are both “close” by this grouping even though one is almost twice the other, so if the exact number matters to you (for school-year planning, for example), the precise years\/months\/days figure is more useful than the category label.<\/p>\n
Sibling A was born March 10, 2012. Sibling B was born September 22, 2016.<\/p>\n
Our Age Gap Calculator<\/a> does the full date-to-date subtraction automatically, so you get the exact years, months, and days between any two people, siblings included, without doing the year-only shortcut that can be off by months.<\/p>\n Count the years, months and days between the two full birth dates rather than subtracting birth years. Year-only subtraction can be off by almost a full year.<\/p>\n There’s no official definition, but a gap under 2 years is commonly called close, 2 to 4 years moderate, and more than 4 years wide.<\/p>\n The World Health Organization recommends waiting at least 24 months after a live birth before trying to conceive again, to reduce health risks for mother and baby.<\/p>\n Subtracting birth years alone can be off by almost a year. Here’s how to get a sibling age gap right, and what counts as a close, moderate, or wide gap.<\/p>\n","protected":false},"author":1,"featured_media":1020,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-94","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-date-time"],"_links":{"self":[{"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/posts\/94","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/comments?post=94"}],"version-history":[{"count":3,"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/posts\/94\/revisions"}],"predecessor-version":[{"id":202,"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/posts\/94\/revisions\/202"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/media\/1020"}],"wp:attachment":[{"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/media?parent=94"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/categories?post=94"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/thenesttools.com\/blog\/wp-json\/wp\/v2\/tags?post=94"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Frequently Asked Questions<\/h2>\n
How do you calculate the age gap between siblings?<\/h3>\n
What is considered a close sibling age gap?<\/h3>\n
What birth spacing do health organisations recommend?<\/h3>\n
Related Reading<\/h2>\n
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