Ada Lovelace Day – 14 October 2025
Ada Lovelace Day (ALD) is an international celebration of the achievements of women in science, technology, engineering and maths (STEM). It aims to increase the profile of women in STEM and, in doing so, create new role models who will encourage more girls into STEM careers and support women already working in STEM. Founded in 2009 by Suw Charman-Anderson, it is now held every year on the second Tuesday of October.
This year, celebrate by organising your own events, at school, work, in your community, at your library or university!
Since 2010, Ada Lovelace Day has included dozens of grassroots events around the world, organised by independent groups who want to support women in STEM in their communities. These events take many forms — from conferences to Wikipedia ‘edit-a-thons’ to pub quizzes — and appeal to all ages, from girls to university students to women with well-established careers.
The Enchantress of Numbers
She conjures numbers in the night;
they bow and dance before their queen,
who labours hard by candle-light
at work the world has not yet seen.
She brings the future into sight
and contemplates the new machine.
The digits fall beneath her spell,
no less in beauty than an ode;
her father's child, she knows so well
imagination's open road.
It leads where only time will tell,
this magic trail she lays with code.
Brian Bilston
Reproduced with kind permission.
Right: Portrait of Ada Lovelace by Margaret Sarah Carpenter, 1836.
Posters, notebooks, greetings cards
You can now buy Ada Lovelace posters, prints, greetings cards, and notebooks from our RedBubble shop! We have a full range of merchandise featuring Ada Lovelace and palaeontologist Mary Anning, plus our two careers posters available for sale.
All profits go to supporting Ada Lovelace Day, and we'll be adding to our range over coming months.
Our Passion for Science
Our mission at Ada Lovelace Day is to raise the profile of women in STEM, and we think our two anthologies about the inventors, pioneers, technologists, scientists, engineers and mathematicians, both modern and historic, do exactly that! Indeed, only one thing unites these stories, whether it is the ground-breaking use of scuba diving to study sharks, or the rigorous physical and psychological testing of Mercury astronaut hopefuls — all our protagonists are women.
A Passion for Science: Stories of Discovery and Invention brings together inspiring stories of how we achieved some of the most important breakthroughs in science and technology, from the identification of the Horsehead Nebula to the creation of the computer program, from the development of in vitro fertilisation to the detection of pulsars.
Journalist and TV presenter Maggie Philbin said that the book is "a brilliant read" and a "powerful, important and engaging record of women’s experiences in science and technology. Some stories I thought I knew, others were completely fresh to me, but every one captured the spirit of a woman I would have loved to have been."
Read our sample chapters, or buy the ebook on Amazon for £1.99.
Our second book, More Passion for Science: Journeys Into the Unknown, explores topics as diverse as the Air Transport Auxiliary ferrying planes around the UK during the Second World War under incredibly dangerous conditions, the programming of the first electronic general purpose computer, and the building of the Brooklyn Bridge.
“This is a wonderful collection of stories written with charm and eloquence by a wonderful collection of people," said mathematician and broadcaster Dr Hannah Fry. "There are captivating tales of celebrated characters and intriguing hidden stories from those sidelined from the spotlight."
Again, you can read some sample chapters, or buy the ebook on Amazon.
From Kiribati to Howland Island
In the middle of the Pacific Ocean, on Kiritimati Island, Ada Lovelace Day begins. Also known as Christmas Island, the coral atoll is situated in the Line Islands and is a part of the Republic of Kiribati. It lies 14 hours ahead of GMT/UTC, and 13 hours ahead of British Summer Time.
It continues for a mindbending 50 hours, until midnight on Baker Island and Howland Island, two uninhabited atolls which are actually further west than Kiritimati Island but which sit on the other side of the International Date Line. Both islands are 12 hours behind GMT/UTC, or 13 hours behind BST.
Who was Ada Lovelace?
Born in 1815, Ada Lovelace collaborated with inventor Charles Babbage on his general purpose computing machine, the Analytical Engine. In 1843, Lovelace published what we would now call a computer program to generate Bernoulli Numbers. Whilst Babbage had written fragments of programs before, Lovelace's was the most complete, most elaborate and the first published.
More importantly, Lovelace was the first person to foresee the creative potential of the Engine. She explained how it could do so much more than merely calculate numbers, and could potentially create music and art, given the right programming and inputs. Her vision of computing's possibilities was unmatched by any of her peers and went unrecognised for a century. Read our biography of Lovelace to find out more!
Why October?
People often ask why Ada Lovelace Day is the day that it is. The explanation is rather mundane: the date is arbitrary, chosen in an attempt to make the day maximally convenient for the most number of people. We have tried to avoid major public holidays, school holidays, exam season, and times of the year when people might be hibernating, so we use the second Tuesday in October.
Why not just used Ada's birthday? Well, Ada was born on 10 December and, in the UK where Ada Lovelace Day is based, December is swamped by Christmas parties, making venue hire tricky and putting us in competition with traditionally unmissable employee booze-ups. Given her tragically early death at just 36, it would feel inappropriate to celebrate her deathday on 27 November.