Second in the world at sixteen
The 2010 Mental Calculation World Cup produced a runner-up who was still at school. Marc Jornet Sanz, from Spain, placed second overall at sixteen and, in the same competition, broke the world record for multiplying two eight-digit numbers — the discipline that separates genuine calculators from quick arithmeticians, because the intermediate products have to be held in memory while the next ones are computed.
The event drew outside attention that year. The Daily Beast published an account of the competition on 11 June 2010 under the headline "The World Championship of Math", written by Alex Bellos. It is the rare case of a mainstream outlet covering a discipline whose results usually live only on the organisers' own site.
Dresden, 2014: the numbers
The 2014 World Cup was held at the Erlebnisland Mathematik in Dresden from 10 to 12 October. The official results put Jornet Sanz second overall in the combination standing with 559.85 points, behind Granth Thakkar of India on 577.77 and ahead of Chie Ishikawa of Japan on 552.02.
The breakdown is more revealing than the total. He won the calendar-calculation category with 64 points and took first place in multiplying eight-digit numbers; in square roots of six-digit numbers he was fifth. A World Cup is not won by being uniformly excellent but by being outstanding in enough disciplines to survive the combination score.
The calendar specialist
Calendar calculation is the event that looks like a party trick and is not. Competitors are given dates anywhere between 1600 and 2100 and must name the weekday for as many as possible in one minute. Doing it at speed requires a memorised century and month structure plus enough spare capacity to keep counting while the next date is read.
This became Jornet Sanz's signature. He won the category at Dresden in 2014, and the record used here shows him winning the calendar-calculation category again at the 2018 World Cup. In November 2018 the specialist site World Mental Calculation published an interview with him, which is the closest thing to a first-person account of his methods in the public record.
What is documented — and what is not
Documented: second place overall in 2010 at sixteen, with a world record in eight-digit multiplication; second overall in 2014 at Dresden with 559.85 points; category wins at Dresden in calendar calculation and multiplication; a fifth place in square roots; a calendar-category win in 2018; and a published interview in November 2018.
Not documented in the sources used here: his date of birth beyond the year implied by his reported age; his education and profession; whether the 2010 multiplication record still stands; and his competitive activity after 2018. Mental calculation keeps immaculate records of results and almost none of the people who set them.
What the World Cup actually measures
The Mental Calculation World Cup runs on five fixed tasks, each of them timed and none of them negotiable. Competitors add ten ten-digit numbers, ten tasks in seven minutes. They multiply two eight-digit numbers, ten tasks in ten minutes. They extract square roots from six-digit numbers, ten tasks in ten minutes. They name weekdays for calendar dates for one minute. A combination score ranks them overall.
A sixth title, Most Versatile Calculator, is decided on surprise tasks the organisers do not announce in advance, which is the only part of the competition that cannot be drilled. The design is deliberate: the fixed events reward years of practice, the surprise events reward whatever is left when practice runs out. Finishing second in that system twice, eight years apart, is a harder thing than a single spectacular record.
| 人物 | 国 | 節目 | 年齢 / 記録 |
|---|---|---|---|
| Wenzel Grüß | ドイツ | 2018年暗算世界選手権、最も多才な計算者 | 9歳 |
| Andrej Živanović | セルビア | ジュニア暗算世界選手権タイトル | 11歳 |
| Marc Jornet Sanz | スペイン | 2010年・2014年暗算世界選手権準優勝 | 16歳 |
| Willem Bouman | オランダ | 70年にわたる暗算、2024年世界選手権の最高齢参加者 | 20歳 |
| Freddis Reyes Hernández | キューバ | 2012年世界選手権での掛け算優勝およびメモリアドトロフィー | 27歳 |
What is documented — and what is not
✓ Documented
- Second overall at the 2014 Mental Calculation World Cup in Dresden with 559.85 points (official results).
- First place at Dresden in calendar calculation (64 points) and in multiplying eight-digit numbers; fifth in square roots.
- Second overall at the 2010 World Cup aged sixteen, with a world record in eight-digit multiplication.
- Won the calendar-calculation category at the 2018 World Cup.
? Unverified, disputed or wrong
- His date of birth, education and profession are not documented in the sources used here.
- It is not stated whether his 2010 multiplication record still stands.
- No competitive results after 2018 are recorded here.
- The Daily Beast article's specific claims about him were not re-read for this page; the citation records the event coverage.
Questions people ask about Marc Jornet Sanz
What is Marc Jornet Sanz known for?
Mental calculation. He finished second overall at the 2010 Mental Calculation World Cup at sixteen and second again in Dresden in 2014, winning individual categories at both.
What world record does he hold?
The sources credit him with breaking the world record for multiplying two eight-digit numbers at the 2010 World Cup. Whether it still stands is not stated.
How did he score at the 2014 World Cup?
559.85 points overall, second behind Granth Thakkar of India (577.77), with first places in calendar calculation and eight-digit multiplication.
What is calendar calculation?
Competitors name the weekday for dates between 1600 and 2100, scoring as many correct answers as they can in one minute.
How old is Marc Jornet Sanz?
He was sixteen at the 2010 World Cup, which implies a birth year around 1994. No source used here gives a date of birth.
Is Marc Jornet Sanz on Wikipedia?
No. There is no Wikipedia article about him; his record is held in the official World Cup results and a 2018 interview.
Where is Marc Jornet Sanz now?
The most recent documented activity here is his 2018 calendar-category win and the interview published that November. Nothing later is established.
Quick quiz: how well do you know Marc’s story?
Where did Marc Jornet Sanz finish at the 2014 World Cup?
Which category did he win in both 2014 and 2018?
How long do competitors get for the calendar event?
Sources
- The World Championship of Math — The Daily Beast, 2010-06-11
- Mental Calculation World Cup 2014 — Results — Mental Calculation World Cup (official), 2014-10
- Marc Jornet Sanz interview — World Mental Calculation, 2018-11-03
Checked by the Geniuses.club editorial team. Ages are given as of September 2026.
