Three podiums
In 2024, at the championship in Bielefeld from 21 to 23 September, Ksentini took silver in the under-20 senior division with 2,580 points, behind Abhilakshya Arora of India on 2,730. The organisers noted he had improved his own score by more than 500 points on the previous year.
In 2025 he scored 2,681 for silver again, behind Kaloyan Geshev of Bulgaria on 2,911 — an improvement of more than 100 points. In 2026 he scored 2,853 and finished third, behind Geshev on 3,045 and Arora on 2,965.
Running to stand still
Between 2024 and 2026 he added 273 points to his total and lost a place. That is not a decline; it is what happens in a discipline where the leading competitors are improving by a hundred points or more a year and the maximum available score keeps rising with the difficulty of the paper.
The published maximums make it measurable: 2,866 in 2024, 2,965 in 2025, and higher still in 2026, when the winner scored 3,045. A competitor who stands still in this environment does not finish fourth. He disappears from the table entirely.
What the championship involves
Competitors work through addition problems, square-root identification, calendar calculations and fraction and multiplication tasks, each timed and marked against a published ceiling. Scores are therefore comparable between competitors, divisions and years.
The event has grown steadily: 84 competitors from 14 nations in 2024, about 80 from 15 in 2025, and 99 from 15 nations — including Algeria, Bulgaria, India, Japan, Lebanon, Serbia and Turkmenistan — over four days in September 2026. It is the junior feeder for the senior Mental Calculation World Cup, and the age divisions run from under-12 to under-20 with a separate category for former competitors.
Algeria at the top table
Ksentini is part of a national cohort rather than an isolated case. Algerian competitors took the top two places in the under-12 division in 2024 and 2025, second and third in the under-15s in 2025, and a podium place in all three junior divisions in 2026.
For a sport whose history was written in Germany, Japan and India, that is a genuine shift. Algeria now sends competitors who expect to medal rather than to attend, and it does so across every age bracket rather than through one exceptional child.
What is documented — and what is not
Documented: silver in the under-20 division in 2024 with 2,580 points, silver in 2025 with 2,681, bronze in 2026 with 2,853, and year-on-year improvements of more than 500 and more than 100 points respectively.
Not documented in these sources: his age, his birth year, his home town, his studies and how he trains. As with every junior competitor on this page, the organisers publish the scores and nothing more, and nothing more is claimed here. Three dated medals and three rising totals are the whole of the verifiable file.
| Person | Country | Milestone | Age / Stat |
|---|---|---|---|
| Wenzel Grüß | Germany | Most Versatile Calculator, 2018 Mental Calculation World Cup | Age 9 |
| Andrej Živanović | Serbia | Junior Mental Calculation World Championship titles | Age 11 |
| Marc Jornet Sanz | Spain | Second place at the 2010 and 2014 Mental Calculation World Cups | Age 16 |
| Freddis Reyes Hernández | Cuba | Winning multiplication and the Memoriad Trophy at the 2012 Mental… | Age 27 |
| Walid Ksentini | Algeria | Three consecutive under-20 medals at the Junior Mental Calculation World… | — |
What is documented — and what is not
✓ Documented
- He took under-20 silver in 2024 with 2,580 points and in 2025 with 2,681 points.
- He took under-20 bronze in 2026 with 2,853 points.
- The organisers recorded improvements of more than 500 points in 2024 and more than 100 in 2025.
- The 2026 championship drew 99 competitors from 15 nations to Bielefeld.
? Unverified, disputed or wrong
- His age, birth year and home town.
- His studies and training methods.
- His results before 2024.
- Whether he will move up to the senior World Cup.
Questions people ask about Walid Ksentini
What has Walid Ksentini won?
Three consecutive medals in the under-20 division of the Junior Mental Calculation World Championship: silver in 2024, silver in 2025 and bronze in 2026.
How old is Walid Ksentini?
The sources used here do not give his age or birth year. He has competed in the under-20 division.
Did his results get worse?
No. His score rose every year — 2,580, 2,681, 2,853 — but the competitors above him improved faster, so his medal colour changed.
Who beat him?
Abhilakshya Arora of India in 2024, and Kaloyan Geshev of Bulgaria in 2025 and 2026, with Arora second in 2026.
What does the competition involve?
Timed addition, square roots, calendar calculation and fraction and multiplication tasks, marked against a published maximum score.
Where is the championship held?
Bielefeld, Germany, in each of the years covered here.
Is Walid Ksentini on Wikipedia?
The research record finds no article under his name. His results are published by the competition organisers.
How is Algeria doing in the sport?
Strongly. Algerian competitors reached the podium in all three junior age divisions at the 2026 championship.
Quick quiz: how well do you know Walid’s story?
How many consecutive medals has Walid Ksentini won?
What was his 2026 score?
Why did his medal colour change in 2026?
Sources
- Junior Mental Calculation World Championship 2024: Results — World Mental Calculation, 2024-09-29
- Junior Mental Calculation World Championship 2025: Results — World Mental Calculation, 2025-10-15
- Junior Mental Calculation World Championship 2026: Results — World Mental Calculation, 2026-09-15
Checked by the Geniuses.club editorial team. Ages are given as of September 2026.
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