Dr Tom Crawford
@tomrocksmaths.bsky.social
Mathematician at Oxford and Cambridge. 225,000 on YouTube. Numberphile. Tom Rocks Maths. Countdown.
Final hike in Oman to the breathtaking Wadi Nakhr - swipe to see video footage of some rather sketchy climbs… A total of 51.42 km covered in 12 hours 53 minutes across 3 separate treks. Is the average velocity above or below 4 km/h?
Try to estimate first before checking on a calculator!
Try to estimate first before checking on a calculator!
November 29, 2025 at 9:39 PM
Final hike in Oman to the breathtaking Wadi Nakhr - swipe to see video footage of some rather sketchy climbs… A total of 51.42 km covered in 12 hours 53 minutes across 3 separate treks. Is the average velocity above or below 4 km/h?
Try to estimate first before checking on a calculator!
Try to estimate first before checking on a calculator!
So much to see in Muscat - from the old town forts and palace, to the Royal Opera House and Grand Mosque.
The population has exploded in the last 75 years from only ~10,000 in 1950 to 1.7 million in 2025, an average increase of 22,500 per year which continues today. Crazy.
The population has exploded in the last 75 years from only ~10,000 in 1950 to 1.7 million in 2025, an average increase of 22,500 per year which continues today. Crazy.
November 28, 2025 at 3:46 PM
So much to see in Muscat - from the old town forts and palace, to the Royal Opera House and Grand Mosque.
The population has exploded in the last 75 years from only ~10,000 in 1950 to 1.7 million in 2025, an average increase of 22,500 per year which continues today. Crazy.
The population has exploded in the last 75 years from only ~10,000 in 1950 to 1.7 million in 2025, an average increase of 22,500 per year which continues today. Crazy.
Great to be back underwater, and what a place to do it! Daymaniyat Islands off the coast of Oman - simply stunning.
Pressure is inversely proportional to volume and doubles approximately every 10m. If I’m diving at a depth of 20m, how much space does 100 cm^3 of air on the surface now take up?
Pressure is inversely proportional to volume and doubles approximately every 10m. If I’m diving at a depth of 20m, how much space does 100 cm^3 of air on the surface now take up?
November 27, 2025 at 1:26 PM
Great to be back underwater, and what a place to do it! Daymaniyat Islands off the coast of Oman - simply stunning.
Pressure is inversely proportional to volume and doubles approximately every 10m. If I’m diving at a depth of 20m, how much space does 100 cm^3 of air on the surface now take up?
Pressure is inversely proportional to volume and doubles approximately every 10m. If I’m diving at a depth of 20m, how much space does 100 cm^3 of air on the surface now take up?
NEW VIDEO: Watch a real example of what an undergraduate admissions interview at the University of Cambridge is like. Can you solve any of the questions?
Premieres today at 5pm (GMT) - see you in the live chat!
Best of luck to anyone being interviewed next month - we're all rooting for you :)
Premieres today at 5pm (GMT) - see you in the live chat!
Best of luck to anyone being interviewed next month - we're all rooting for you :)
University of Cambridge Maths Admissions Interview
YouTube video by Tom Rocks Maths
www.youtube.com
November 26, 2025 at 2:36 PM
NEW VIDEO: Watch a real example of what an undergraduate admissions interview at the University of Cambridge is like. Can you solve any of the questions?
Premieres today at 5pm (GMT) - see you in the live chat!
Best of luck to anyone being interviewed next month - we're all rooting for you :)
Premieres today at 5pm (GMT) - see you in the live chat!
Best of luck to anyone being interviewed next month - we're all rooting for you :)
Exploring the sights in Oman: Jabreen Castle, Nizwa Souq, and Bahla Fort. Human habitation here stretches back over 100,000 years - the half way point between today and the emergence of the Homo Sapiens species ~200,000 years ago.
November 25, 2025 at 1:45 PM
Exploring the sights in Oman: Jabreen Castle, Nizwa Souq, and Bahla Fort. Human habitation here stretches back over 100,000 years - the half way point between today and the emergence of the Homo Sapiens species ~200,000 years ago.
The most votes in a round so far leads to another well-deserved win for @susiedent.com and the "lost positives".
Words now have a potentially unassailable lead at 8-4 so I'd better bring my prime game to the next few rounds if Numbers are going to catch up... new video coming soon!
Words now have a potentially unassailable lead at 8-4 so I'd better bring my prime game to the next few rounds if Numbers are going to catch up... new video coming soon!
November 24, 2025 at 7:02 PM
The most votes in a round so far leads to another well-deserved win for @susiedent.com and the "lost positives".
Words now have a potentially unassailable lead at 8-4 so I'd better bring my prime game to the next few rounds if Numbers are going to catch up... new video coming soon!
Words now have a potentially unassailable lead at 8-4 so I'd better bring my prime game to the next few rounds if Numbers are going to catch up... new video coming soon!
Highest point in Oman at 3018m - WHAT A VIEW. Not quite 500 miles, but 24.5 km covered in 7 hours makes one tired Tom. Now to go lie down…
Well done to those of you that guessed Oman from yesterday’s post, excellent detective work :)
Well done to those of you that guessed Oman from yesterday’s post, excellent detective work :)
November 23, 2025 at 4:37 PM
Highest point in Oman at 3018m - WHAT A VIEW. Not quite 500 miles, but 24.5 km covered in 7 hours makes one tired Tom. Now to go lie down…
Well done to those of you that guessed Oman from yesterday’s post, excellent detective work :)
Well done to those of you that guessed Oman from yesterday’s post, excellent detective work :)
You all seemed to enjoy this last time, so can you guess where I am? Canyons, desert, and goats galore. Answer to be revealed tomorrow :)
November 22, 2025 at 3:59 PM
You all seemed to enjoy this last time, so can you guess where I am? Canyons, desert, and goats galore. Answer to be revealed tomorrow :)
NEW VIDEO (from Dr Zye): Can You Draw Every Flag in Powerpoint?
The winning essay from the 2025 Tom Rocks Maths Essay Competition has been turned into a video - and it's one of the best things I've ever seen. Go watch now.
The winning essay from the 2025 Tom Rocks Maths Essay Competition has been turned into a video - and it's one of the best things I've ever seen. Go watch now.
Can You Draw Every Flag in Powerpoint? (Part 1)
YouTube video by Dr. Zye
www.youtube.com
November 21, 2025 at 8:51 PM
NEW VIDEO (from Dr Zye): Can You Draw Every Flag in Powerpoint?
The winning essay from the 2025 Tom Rocks Maths Essay Competition has been turned into a video - and it's one of the best things I've ever seen. Go watch now.
The winning essay from the 2025 Tom Rocks Maths Essay Competition has been turned into a video - and it's one of the best things I've ever seen. Go watch now.
Such a fun day of filming with an actual green screen (so much better than my attempts) on an exciting new project! Looking forward to sharing the outcome with you all over the next few months :)
November 20, 2025 at 5:17 PM
Such a fun day of filming with an actual green screen (so much better than my attempts) on an exciting new project! Looking forward to sharing the outcome with you all over the next few months :)
Happy Maths Week England!! It’s been a busy few days travelling across the country to reach as many students - and teachers - as possible to celebrate all things maths. From Mario vs Sonic, to Pokemon in space, maths is everywhere. Search Maths Week England to find events happening near you :)
November 19, 2025 at 9:40 PM
Happy Maths Week England!! It’s been a busy few days travelling across the country to reach as many students - and teachers - as possible to celebrate all things maths. From Mario vs Sonic, to Pokemon in space, maths is everywhere. Search Maths Week England to find events happening near you :)
Tattoo #65 - Leaf Badge. I’ve spent a lot of time talking about the maths of Pokémon the last few weeks on the road, as well as writing about the game for my upcoming book, so this feels like a highly appropriate post. I make it 5 Kanto badges posted so far, which means 3 more to come :)
November 18, 2025 at 9:42 PM
Tattoo #65 - Leaf Badge. I’ve spent a lot of time talking about the maths of Pokémon the last few weeks on the road, as well as writing about the game for my upcoming book, so this feels like a highly appropriate post. I make it 5 Kanto badges posted so far, which means 3 more to come :)
Had a great time at Scarisbrick Hall School today talking million-dollar equations and mathematical modelling in sport with years 7-13 (look how excited they are in the last photo!). And what a beautiful building for a school - definite Hogwarts vibes <3
November 17, 2025 at 7:51 PM
Had a great time at Scarisbrick Hall School today talking million-dollar equations and mathematical modelling in sport with years 7-13 (look how excited they are in the last photo!). And what a beautiful building for a school - definite Hogwarts vibes <3
Tom Rocks Maths going international with a recent article in Dutch newspaper Trouw about the use of mathematical modelling in sports including rowing, running, football, basketball and cricket.
Translated version available at the link below - enjoy!
tomrocksmaths.com/2025/11/16/t...
Translated version available at the link below - enjoy!
tomrocksmaths.com/2025/11/16/t...
November 16, 2025 at 5:51 PM
Tom Rocks Maths going international with a recent article in Dutch newspaper Trouw about the use of mathematical modelling in sports including rowing, running, football, basketball and cricket.
Translated version available at the link below - enjoy!
tomrocksmaths.com/2025/11/16/t...
Translated version available at the link below - enjoy!
tomrocksmaths.com/2025/11/16/t...
NEW VIDEO: Numbers vs. Words Round 12 - Ruthful vs. 117 billion.
Lost positives from @susiedent.com versus the number of humans that have ever lived from Dr Tom.
Vote for your favourite here: forms.gle/83C1LHbqUw6r...
Lost positives from @susiedent.com versus the number of humans that have ever lived from Dr Tom.
Vote for your favourite here: forms.gle/83C1LHbqUw6r...
Numbers vs. Words Round 12: Ruthful vs. 117 Billion
YouTube video by Tom Rocks Maths
www.youtube.com
November 14, 2025 at 5:51 PM
NEW VIDEO: Numbers vs. Words Round 12 - Ruthful vs. 117 billion.
Lost positives from @susiedent.com versus the number of humans that have ever lived from Dr Tom.
Vote for your favourite here: forms.gle/83C1LHbqUw6r...
Lost positives from @susiedent.com versus the number of humans that have ever lived from Dr Tom.
Vote for your favourite here: forms.gle/83C1LHbqUw6r...
Some highlights from the past few days: Maths in Action London; YouTube learning roundtable at Google UK; and inspiring future mathematicians at the Norfolk Maths Symposium in Norwich. I love this job <3
November 13, 2025 at 8:35 PM
Some highlights from the past few days: Maths in Action London; YouTube learning roundtable at Google UK; and inspiring future mathematicians at the Norfolk Maths Symposium in Norwich. I love this job <3
A final Sri Lanka appreciation post full of tea, waterfalls, and a sweaty mid-run Dr Tom.
Sri Lanka is the world’s 4th largest producer of tea, with China topping the charts at 10x the amount. World production is 30 million tonnes, SL and China together account for 55%, so how much does SL produce?
Sri Lanka is the world’s 4th largest producer of tea, with China topping the charts at 10x the amount. World production is 30 million tonnes, SL and China together account for 55%, so how much does SL produce?
November 12, 2025 at 10:16 PM
A final Sri Lanka appreciation post full of tea, waterfalls, and a sweaty mid-run Dr Tom.
Sri Lanka is the world’s 4th largest producer of tea, with China topping the charts at 10x the amount. World production is 30 million tonnes, SL and China together account for 55%, so how much does SL produce?
Sri Lanka is the world’s 4th largest producer of tea, with China topping the charts at 10x the amount. World production is 30 million tonnes, SL and China together account for 55%, so how much does SL produce?
Are you even a tourist in Sri Lanka if you don’t take the train ride across the mountains to Ella? Simply breathtaking.
It took 7 hours and 20 minutes to travel from Nanu Oya to Colombo at an average speed of 28 kmph. How long is the railway?
Try it without a calculator for a challenge :)
It took 7 hours and 20 minutes to travel from Nanu Oya to Colombo at an average speed of 28 kmph. How long is the railway?
Try it without a calculator for a challenge :)
November 11, 2025 at 5:42 PM
Are you even a tourist in Sri Lanka if you don’t take the train ride across the mountains to Ella? Simply breathtaking.
It took 7 hours and 20 minutes to travel from Nanu Oya to Colombo at an average speed of 28 kmph. How long is the railway?
Try it without a calculator for a challenge :)
It took 7 hours and 20 minutes to travel from Nanu Oya to Colombo at an average speed of 28 kmph. How long is the railway?
Try it without a calculator for a challenge :)
Reposted by Dr Tom Crawford
Behind the scenes of the recording session with @tomrocksmaths.bsky.social for the @twinklresources.bsky.social "Leading With" podcast today where Tom shared his insights into engaging people in maths as well as what he learned from sitting GCSE exams and deputising for Rachel Riley on Countdown!
November 11, 2025 at 4:38 PM
Behind the scenes of the recording session with @tomrocksmaths.bsky.social for the @twinklresources.bsky.social "Leading With" podcast today where Tom shared his insights into engaging people in maths as well as what he learned from sitting GCSE exams and deputising for Rachel Riley on Countdown!
Loved catching up with Prof. Alison Martingano and talking about how to overcome maths anxiety on the Psychology & Stuff podcast at UWGB. We went to the same high school but hadn't seen each other in 20 years... amazing to reconnect after all this time!
Listen here: soundcloud.com/rycmart/ep-1...
Listen here: soundcloud.com/rycmart/ep-1...
November 9, 2025 at 5:57 PM
Loved catching up with Prof. Alison Martingano and talking about how to overcome maths anxiety on the Psychology & Stuff podcast at UWGB. We went to the same high school but hadn't seen each other in 20 years... amazing to reconnect after all this time!
Listen here: soundcloud.com/rycmart/ep-1...
Listen here: soundcloud.com/rycmart/ep-1...
Linguistic Fossils take the win over the Birthday Problem - well done again to @susiedent.com
Keep a lookout for a full video explaining the Birthday Problem and 23 - coming soon :)
In the meantime you can catch up on all 11 rounds of "Numbers vs Words" so far here: www.youtube.com/watch?v=4Jev...
Keep a lookout for a full video explaining the Birthday Problem and 23 - coming soon :)
In the meantime you can catch up on all 11 rounds of "Numbers vs Words" so far here: www.youtube.com/watch?v=4Jev...
November 8, 2025 at 4:32 PM
Linguistic Fossils take the win over the Birthday Problem - well done again to @susiedent.com
Keep a lookout for a full video explaining the Birthday Problem and 23 - coming soon :)
In the meantime you can catch up on all 11 rounds of "Numbers vs Words" so far here: www.youtube.com/watch?v=4Jev...
Keep a lookout for a full video explaining the Birthday Problem and 23 - coming soon :)
In the meantime you can catch up on all 11 rounds of "Numbers vs Words" so far here: www.youtube.com/watch?v=4Jev...
NEW VIDEO: The Kissing Coins Problem - what is the smallest circle that encloses three touching coins? Premieres today at 4pm (GMT). See you in the live chat!
The Kissing Coins Problem
YouTube video by Tom Rocks Maths
www.youtube.com
November 7, 2025 at 9:15 AM
NEW VIDEO: The Kissing Coins Problem - what is the smallest circle that encloses three touching coins? Premieres today at 4pm (GMT). See you in the live chat!
Fascinating conversations with some of the greatest minds in Mathematics and Physics at the HKLF - what a couple of days it's been!
1. Reinhard Genzel (2008 Shaw Prize & 2020 Nobel Prize)
2. Nigel J Hitchin (2016 Shaw Prize)
3. John Peacock (2014 Shaw Prize)
4. Simon D M White (2017 Shaw Prize)
1. Reinhard Genzel (2008 Shaw Prize & 2020 Nobel Prize)
2. Nigel J Hitchin (2016 Shaw Prize)
3. John Peacock (2014 Shaw Prize)
4. Simon D M White (2017 Shaw Prize)
November 6, 2025 at 4:53 PM
Fascinating conversations with some of the greatest minds in Mathematics and Physics at the HKLF - what a couple of days it's been!
1. Reinhard Genzel (2008 Shaw Prize & 2020 Nobel Prize)
2. Nigel J Hitchin (2016 Shaw Prize)
3. John Peacock (2014 Shaw Prize)
4. Simon D M White (2017 Shaw Prize)
1. Reinhard Genzel (2008 Shaw Prize & 2020 Nobel Prize)
2. Nigel J Hitchin (2016 Shaw Prize)
3. John Peacock (2014 Shaw Prize)
4. Simon D M White (2017 Shaw Prize)
Back at the Hong Kong Laureate Forum to interview 4 Shaw Laureates over the next few days. Love visiting this city, especially the harbour - just look at that skyline <3
With a population of 7.5 million and occupied apartment space of 112.5 million m2, how big is the average apartment per person?
With a population of 7.5 million and occupied apartment space of 112.5 million m2, how big is the average apartment per person?
November 5, 2025 at 5:04 PM
Back at the Hong Kong Laureate Forum to interview 4 Shaw Laureates over the next few days. Love visiting this city, especially the harbour - just look at that skyline <3
With a population of 7.5 million and occupied apartment space of 112.5 million m2, how big is the average apartment per person?
With a population of 7.5 million and occupied apartment space of 112.5 million m2, how big is the average apartment per person?
Sigiriya, Sri Lanka. An ancient rock fortress built in the 5th Century. The hydrodynamic system connecting the water gardens is phenomenal, not to mention the lions paw, and views at the top of the 1200 steps. If I climb 90 steps per minute, how long does it take me to get to the top?
November 4, 2025 at 1:39 PM
Sigiriya, Sri Lanka. An ancient rock fortress built in the 5th Century. The hydrodynamic system connecting the water gardens is phenomenal, not to mention the lions paw, and views at the top of the 1200 steps. If I climb 90 steps per minute, how long does it take me to get to the top?