Tokyo Journal of Mathematics
- ISSN-L
- 0387-3870
- OpenAlex ID
- S56024765
- APC list price
- Not listed
In 2025, Tokyo Journal of Mathematics had an OJR of 0.31: its 2022–2024 papers received 31% of the world-average citations for comparable papers. Its Impact factor (2-year) was 0.20. Both figures are calculated from OpenAlex data.
Tokyo Journal of Mathematics is Q4 in OpenJournalRank’s 2025 Geometry and Topology ranking (#106 of 137 eligible journals). These are OJR quartiles, calculated independently of SCImago, Scopus and JCR quartiles.
The OpenJournalRank Indicator (OJR) is a free, publicly available metric of a journal’s field-normalized citation impact, computed from open OpenAlex citation data. It compares citations to a journal’s papers from the previous three years with the world average for papers of the same subfield, year and type, so 1.00 is the world average and values can be compared across fields. It is computed with the NCI3 method. For 2025 it counts non-self citations to the articles, reviews and conference papers a journal published in 2022–2024. Ranks and quartiles order journals by OJR within the subfield, the field and all journals.
0.31
Q4#106 of 137
The Impact factor (2-year) counts citations made in 2025 to the articles, reviews and conference papers a journal published in the two previous years (2023–2024), divided by the number of those papers. Self-citations count; citations from repository-hosted works do not. It is not normalized by field. Clarivate’s Journal Impact Factor™ uses the same basic formula but gives different numbers, and this site does not show it. Clarivate also counts citations to editorials, news and letters while dividing only by articles and reviews. OpenAlex sets document types automatically. The citing data differ: OpenAlex links references for most but not all works, and we leave out repository-hosted citing works. Publication years and snapshot dates also differ. Because of these differences, our value can be higher or lower than the JIF for a given journal, so don’t compare the two directly.
0.20
-41.3% change from 2024
from 0.34 in 2024
Why is it different?
- Journals usually quote Clarivate’s Journal Impact Factor™ (JIF).
- Same idea: citations this year to papers from the past two years, divided by those papers.
- The JIF also counts citations to editorials, news and letters but divides only by research papers. We count citations to research papers only.
- Different citation data (OpenAlex, not Web of Science) and timing.
So the two numbers can differ, in either direction, and the size of the difference has not been established. Compare ours with other journals here, not with the JIF.
Full explanation →OJR compares non-self citations to classified citable papers with the world-average expectation for their subfields, publication years and types.
Computed by OpenJournalRank from the OpenAlex snapshot of September 23, 2026; 472,521,793 citations counted across this release.
Looking for Clarivate’s Journal Impact Factor™? Check the Master Journal List
OJR rank in each category · 2025
The badge is the quartile; Q1 is the top quarter of ranked journals. Each track runs from the bottom of the category (left) to the top (right), shaded by quartile. The bold marker is this journal and the thin tick the category median. The outlined box is the likely rank range: the 95% interval from re-drawing the journal’s papers 1,000 times. “Spans Q1–Q2” means that range crosses a quartile boundary.
Ranking categories are derived from OpenAlex paper classifications and may differ from a journal’s stated scope.
At a glance
Quartile history in every category and the key figures for 2025, drawn as small charts.
Quartile by year
Each cell is the journal’s quartile among ranked journals in that category and year, by OJR. Q1 is the top quarter. Years run 2000–2025; tap or hover a cell for the exact rank.
2025Subfield · Geometry and TopologyQ4Rank 106 of 137#106 of 137
Each track runs from the bottom of the category (left) to the top (right), shaded by quartile. The bold marker is this journal, the outlined box its likely rank range and the thin tick the category median.
#106 of 137in Geometry and Topology
Citations made in 2025 to papers from 2023–2024, divided by the number of those papers, next to the same value a year earlier.
0.20-41.3%
Everything the journal published in 2025, split into articles, reviews and other items such as editorials. The line shows the last ten years.
29
Citations made in 2025 to papers from 2022–2024, divided by the number of those papers. Includes self-citations. The line shows the last ten years.
0.3
The median number of 2025 citations per paper from 2022–2024, next to the mean (cites per document). A mean far above the median means a few papers draw most of the citations.
0.0
Share of the journal’s 2022–2024 papers that are among the most cited 10% for their subfield, year and type. The marker at 10% is the world baseline.
2.0%
Share of 2025 citations to the journal’s 2022–2024 papers that come from the journal itself. The tick on the ring marks the field median.
5.6%
Share of documents published in 2025 that are free to read, across all document types.
3%
Share of documents published in 2025 with authors in two or more countries.
0%
All-time OpenAlex values at the snapshot date, not limited to the ranking window. The h-index is the largest h such that h papers have at least h citations each; the i10-index counts papers with at least 10 citations.
43h-index
Over the years
Impact factor (2-year)
Show the data as a table
| Year | Impact factor (2-year) |
|---|---|
| 2025 | 0.20 |
| 2024 | 0.34 |
| 2023 | 0.18 |
| 2022 | 0.30 |
| 2021 | 0.33 |
| 2020 | 0.38 |
| 2019 | 0.23 |
| 2018 | 0.22 |
| 2017 | 0.29 |
| 2016 | 0.25 |
| 2015 | 0.31 |
| 2014 | 0.50 |
| 2013 | 0.67 |
| 2012 | 0.34 |
| 2011 | 0.43 |
| 2010 | 0.27 |
| 2009 | 0.30 |
| 2008 | 0.31 |
| 2007 | 0.20 |
| 2006 | 0.21 |
| 2005 | 0.21 |
| 2004 | 0.26 |
| 2003 | 0.53 |
| 2002 | 0.23 |
| 2001 | 0.43 |
| 2000 | 0.20 |
OJR
Show the data as a table
| Year | OJR | Field median |
|---|---|---|
| 2025 | 0.31 | 0.56 |
| 2024 | 0.32 | 0.55 |
| 2023 | 0.21 | 0.51 |
| 2022 | 0.39 | 0.54 |
| 2021 | 0.40 | 0.56 |
| 2020 | 0.33 | 0.62 |
| 2019 | 0.32 | 0.64 |
| 2018 | 0.28 | 0.64 |
| 2017 | 0.40 | 0.69 |
| 2016 | 0.35 | 0.74 |
| 2015 | 0.48 | 0.76 |
| 2014 | 0.70 | 0.80 |
| 2013 | 0.60 | 0.78 |
| 2012 | 0.43 | 0.83 |
| 2011 | 0.38 | 0.86 |
| 2010 | 0.39 | 0.89 |
| 2009 | 0.36 | 0.92 |
| 2008 | 0.29 | 0.89 |
| 2007 | 0.20 | 0.92 |
| 2006 | 0.27 | 0.88 |
| 2005 | 0.39 | 0.85 |
| 2004 | 0.32 | 0.84 |
| 2003 | 0.69 | 0.87 |
| 2002 | 0.41 | 0.80 |
| 2001 | 0.49 | 0.75 |
| 2000 | 0.24 | 0.76 |
Documents by type
Show the data as a table
| Year | Articles | Reviews | Other |
|---|---|---|---|
| 2025 | 29 | 0 | 0 |
| 2024 | 17 | 0 | 1 |
| 2023 | 13 | 0 | 0 |
| 2022 | 31 | 0 | 0 |
| 2021 | 20 | 0 | 0 |
| 2020 | 33 | 0 | 1 |
| 2019 | 27 | 0 | 0 |
| 2018 | 31 | 0 | 0 |
| 2017 | 33 | 0 | 0 |
| 2016 | 41 | 0 | 0 |
| 2015 | 35 | 0 | 0 |
| 2014 | 33 | 0 | 0 |
| 2013 | 31 | 0 | 0 |
| 2012 | 33 | 0 | 0 |
| 2011 | 30 | 0 | 1 |
| 2010 | 32 | 0 | 0 |
| 2009 | 35 | 0 | 0 |
| 2008 | 35 | 0 | 0 |
| 2007 | 39 | 0 | 0 |
| 2006 | 32 | 0 | 0 |
| 2005 | 38 | 0 | 0 |
| 2004 | 40 | 0 | 0 |
| 2003 | 31 | 0 | 0 |
| 2002 | 35 | 0 | 1 |
| 2001 | 45 | 0 | 1 |
| 2000 | 33 | 0 | 0 |
Citations to the previous three years
Show the data as a table
| Year | From other sources | Self-citations |
|---|---|---|
| 2025 | 17 | 1 |
| 2024 | 19 | 1 |
| 2023 | 18 | 1 |
| 2022 | 32 | 2 |
| 2021 | 38 | 2 |
| 2020 | 27 | 5 |
| 2019 | 29 | 1 |
| 2018 | 23 | 4 |
| 2017 | 32 | 2 |
| 2016 | 27 | 2 |
| 2015 | 36 | 2 |
| 2014 | 52 | 1 |
| 2013 | 46 | 3 |
| 2012 | 34 | 3 |
| 2011 | 32 | 3 |
| 2010 | 33 | 2 |
| 2009 | 29 | 2 |
| 2008 | 23 | 2 |
| 2007 | 15 | 8 |
| 2006 | 21 | 1 |
| 2005 | 26 | 3 |
| 2004 | 23 | 4 |
| 2003 | 51 | 5 |
| 2002 | 28 | 2 |
| 2001 | 30 | 5 |
| 2000 | 16 | 4 |
Share in the top 10% of their field
Show the data as a table
| Year | Top 10% share |
|---|---|
| 2025 | 2.0% |
| 2024 | 3.2% |
| 2023 | 2.5% |
| 2022 | 2.9% |
| 2021 | 3.3% |
| 2020 | 4.2% |
| 2019 | 4.6% |
| 2018 | 1.2% |
| 2017 | 2.7% |
| 2016 | 4.1% |
| 2015 | 3.0% |
| 2014 | 6.7% |
| 2013 | 5.4% |
| 2012 | 2.9% |
| 2011 | 3.7% |
| 2010 | 3.4% |
| 2009 | 3.2% |
| 2008 | 2.0% |
| 2007 | 1.0% |
| 2006 | 0.9% |
| 2005 | 3.8% |
| 2004 | 3.9% |
| 2003 | 5.5% |
| 2002 | 3.1% |
| 2001 | 7.8% |
| 2000 | 2.4% |
Collaboration and open access
Show the data as a table
| Year | International collaboration | Open access |
|---|---|---|
| 2025 | 0.0% | 3.4% |
| 2024 | 0.0% | 0.0% |
| 2023 | 0.0% | 7.7% |
| 2022 | 0.0% | 29.0% |
| 2021 | 10.0% | 60.0% |
| 2020 | 5.9% | 79.4% |
| 2019 | 0.0% | 70.4% |
| 2018 | 12.9% | 71.0% |
| 2017 | 6.1% | 69.7% |
| 2016 | 12.2% | 75.6% |
| 2015 | 2.9% | 94.3% |
| 2014 | 15.2% | 90.9% |
| 2013 | 9.7% | 80.6% |
| 2012 | 18.2% | 81.8% |
| 2011 | 19.4% | 74.2% |
| 2010 | 3.1% | 78.1% |
| 2009 | 2.9% | 77.1% |
| 2008 | 14.3% | 77.1% |
| 2007 | 12.8% | 82.1% |
| 2006 | 12.5% | 75.0% |
| 2005 | 2.6% | 86.8% |
| 2004 | 7.5% | 72.5% |
| 2003 | 6.5% | 74.2% |
| 2002 | 11.1% | 72.2% |
| 2001 | 2.2% | 82.6% |
| 2000 | 9.1% | 87.9% |
In context
How Tokyo Journal of Mathematics compares with the journals of its comparison group: Mathematics. Windows are 2022–2024 (retractions 2015–2024).
Each group is the journal’s field, or its domain when the field has too few eligible journals. On each value track the shaded band is the middle half of the group and the tick its median. The percentile under it is a mid-rank position out of 100: journals with a lower value count fully and tied journals count half, so ties share a mid-rank. Colour marks only retractions, cost and an unusual self-citation share; other differences carry no quality judgement.
- This journal
- Median
- Middle half of field
Integrity and cost
Retracted papers per 1,000
Papers marked retracted per 1,000 citable papers at the OpenAlex snapshot date; this does not show the reasons for retraction or assess a journal’s practices.
Comparison group too small or not enough papers for this measure.
Listed APC (USD)
The article processing charge OpenAlex lists for the source; zero means a listed charge of $0.
OpenAlex has no listed APC for this journal, so there is no cost comparison.
Check the publisher’s author guidelines for current charges.
Journal self-citation share
Share of citations to window papers that come from the same journal; a high share can reflect a narrow specialty and is not evidence of misconduct.
Comparison group too small or not enough papers for this measure.
Openness and reach
Open access share
Share of window papers marked open access among papers with known OA status.
Middle half of the field: 33.8%–100.0%; median 57.5%; n = 610 field journals.
Field percentile: 12/100 among 610 eligible journals
12/100International collaboration share
Share of window papers with at least two distinct affiliation countries among papers with a known country.
Comparison group too small or not enough papers for this measure.
Output growth
Change in citable paper counts between two adjacent three-year windows; it does not show changes in research quality or explain why output changed.
Middle half of the field: -16.9%–+21.5%; median -2.1%; n = 575 field journals.
Field percentile: 19/100 among 575 eligible journals
19/100Document mix
Review share
Reviews as a share of all citable window papers.
Middle half of the field: 0.0%–0.0%; median 0.0%; n = 610 field journals.
Field percentile: 46/100 among 610 eligible journals
46/100Articles-only OJR
OJR for classified window articles only, using the same baseline cells as the overall score.
Middle half of the field: 0.37–0.83; median 0.56; n = 610 field journals.
Field percentile: 20/100 among 610 eligible journals
20/100Citation distribution
Uncited share
Share of window papers receiving no non-self citations in the indicator year.
Middle half of the field: 44.7%–69.6%; median 57.3%; n = 610 field journals.
Field percentile: 91/100 among 610 eligible journals
91/100Citation concentration
Share of non-self citations received by the journal’s most-cited 10% of window papers.
Middle half of the field: 45.8%–58.7%; median 52.0%; n = 610 field journals.
Field percentile: 89/100 among 610 eligible journals
89/100Similar journals
Journals ranked nearest to this one in Geometry and Topology by OJR, 2025.
- #101Experimental MathematicsQ3OJR 0.35
- #102Bollettino Della Unione Matematica ItalianaQ3OJR 0.34
- #103Model TheoryQ3OJR 0.33
- #104American Journal of Applied Mathematics and StatisticsQ4OJR 0.33
- #105Fundamenta MathematicaeQ4OJR 0.31
- #106Tokyo Journal of Mathematics (This journal)Q4OJR 0.31
- #107Topology and its ApplicationsQ4OJR 0.31
- #108Moscow Mathematical JournalQ4OJR 0.31
- #109Journal de Théorie des Nombres de BordeauxQ4OJR 0.30
- #110Journal of Mathematical LogicQ4OJR 0.30
- #111Annales mathématiques Blaise PascalQ4OJR 0.29
Detailed breakdown
The figures behind the charts, written out in full.
The two headline numbers
OJR is OpenJournalRank’s index, computed with the NCI3 method. It divides the non-self citations that papers published in 2022–2024 received in 2025 by the citations expected for papers of the same subfield, publication year and type worldwide. For 2022–2024, papers in this journal received 31% of the citations expected worldwide for comparable papers.
The Impact factor (2-year) is simpler: citations made in 2025 to the papers published in 2023 and 2024, divided by the number of those papers. For this journal it was 0.20, down from 0.34 in 2024 (-41.3%). It counts self-citations and is not adjusted for field, so a value of 5 means something different in economics and in molecular biology.
This value is computed from OpenAlex and is not Clarivate’s Journal Impact Factor™. The two use different citation sources and different rules for which items count, so the numbers will not match. Across all core journals, 84.3% of articles and reviews published in 2025 have at least one matched reference in OpenAlex (87.1% in 2024). This is a corpus-wide share: it does not measure how complete any one journal’s reference lists are, and no value on this page is adjusted for it.
In context, in full
Descriptive comparisons with eligible journals ranked in 2025.
| Measure | This journal | Field or domain | Position |
|---|---|---|---|
| Output growthChange in citable paper counts between two adjacent three-year windows; it does not show changes in research quality or explain why output changed. | -23.8%61 papers in the later window; 80 in the earlier window | Field median: -2.1%Mathematics | percentile 19/100 among 575 eligible Mathematics journals19/100 |
| Open access shareShare of window papers marked open access among papers with known OA status. | 16.4%10 of 61 papers with known metadata | Field median: 57.5%Mathematics | percentile 12/100 among 610 eligible Mathematics journals12/100 |
| Review shareReviews as a share of all citable window papers. | 0.0%0 reviews among 61 window papers | Field median: 0.0%Mathematics | percentile 46/100 among 610 eligible Mathematics journals46/100 |
| Articles-only OJRNormalized citation impact of classified window articles, using the same baseline cells as the overall OJR. | 0.3161 classified articles; all papers: 0.31 | Field median: 0.56Mathematics | percentile 20/100 among 610 eligible Mathematics journals20/100 |
| Uncited shareShare of window papers receiving no non-self citations in the indicator year. | 80.3%49 uncited among 61 window papers | Field median: 57.3%Mathematics | percentile 91/100 among 610 eligible Mathematics journals91/100 |
| Citation concentrationShare of non-self citations received by the journal’s most-cited 10% of window papers. | 70.6%12 of 17 non-self citations; top 7 of 61 papers | Field median: 52.0%Mathematics | percentile 89/100 among 610 eligible Mathematics journals89/100 |
Ties share a mid-rank percentile. A higher value carries no quality judgement. How field comparisons work
How this score was computed
Citations made in 2025 to articles, reviews and conference papers published in 2022–2024. Actual and Expected include only papers with a subfield.
- Actual (non-self citations)
- 17
- Expected (world-average expectation)
- 54.759665
- OJR standard error
- 0.1038
- Most-cited paper's share of citations
- 23.5%
- Citable papers in 2022–2024
- 61
- Classification coverage
- 100.0%
- Share of citable papers with a subfield
- Citations without a known source
- 0.0%
- Share of Actual from citing works without a known source
- Reference coverage in 2025
- 84.3%
- Corpus-wide share of core-journal articles and reviews with at least one matched reference
OJR = Actual ÷ Expected
17 ÷ 54.759665 ≈ 0.31
Displayed values are rounded; OJR uses the unrounded expectation.
Impact factor (2-year), 2025 = 6 ÷ 30 = 0.20
Publication window 2023–2024; includes journal self-citations.
What it publishes
In 2022–2024, the journal published 61 citable papers (articles, reviews and conference papers).
Among papers with a subfield: 34% in Geometry and Topology, 25% in Applied Mathematics, 21% in Mathematical Physics, 10% in Algebra and Number Theory, and 3% in Computational Theory and Mathematics.
Subjects follow OpenAlex’s primary-subfield classification, which may differ from a journal’s stated scope.
Among papers with a known author affiliation country: Japan (67%), France (22%), and Italy (11%). Author affiliations span 3 countries in this window. A paper counts toward each country it lists, so shares can total more than 100%.
15% of the window’s citable papers list at least one author affiliation country; country shares describe that subset.
Open-access status among papers with a known status: closed (84%), bronze (13%), and green (3%).