P21

Cyclin dependent kinase inhibitor 1A - mammalian protein found in Homo sapiens. Article “P21” in Czech Wikipedia has 15.7 points for quality (as of July 1, 2025).

This article has the best quality in English Wikipedia. Also, this article is the most popular in that (Czech) language version.

Since the creation of article “P21”, its content was written by 1 registered users of Czech Wikipedia and edited by 174 registered Wikipedia users in all languages.

The article is cited 32 times in Czech Wikipedia and cited 470 times in all languages.

The highest Authors Interest rank from 2001:

• Local (Czech): #26141 in February 2018
• Global: #86336 in April 2013

The highest popularity rank from 2008:

• Local (Czech): #67197 in June 2017
• Global: #130248 in April 2015

There are 15 language versions for this article in the WikiRank database (of the considered 55 Wikipedia language editions).

The quality and popularity assessment was based on Wikipédia dumps from July 1, 2025 (including revision history and pageviews for previous years).

The table below shows the language versions of the article with the highest quality.

#	Language	Quality grade	Quality score
1	English (en) P21		78.4423
2	Polish (pl) P21		36.2179
3	Japanese (ja) P21		34.8817
4	Italian (it) P21		33.4227
5	French (fr) P21		27.3131
6	German (de) CDK-Inhibitor 1		21.7045
7	Ukrainian (uk) CDKN1A		21.2125
8	Spanish (es) P21		16.8012
9	Czech (cs) P21		15.6521
10	Russian (ru) CDKN1A		15.1516

More...

The following table shows the most popular language versions of the article.

The most popular language versions of the article "P21" in all the time

#	Language	Popularity award	Relative popularity
1	English (en) P21		1 170 101
2	Spanish (es) P21		122 340
3	Japanese (ja) P21		107 505
4	Italian (it) P21		76 141
5	German (de) CDK-Inhibitor 1		63 767
6	Polish (pl) P21		56 591
7	Portuguese (pt) P21		36 001
8	French (fr) P21		29 803
9	Russian (ru) CDKN1A		25 236
10	Korean (ko) P21		22 034

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The following table shows the language versions of the article with the highest popularity in the last month.

The most popular language versions of the article "P21" in June 2025

#	Language	Popularity award	Relative popularity
1	English (en) P21		1 407
2	Japanese (ja) P21		187
3	Spanish (es) P21		125
4	Italian (it) P21		109
5	German (de) CDK-Inhibitor 1		94
6	Korean (ko) P21		89
7	French (fr) P21		84
8	Polish (pl) P21		57
9	Russian (ru) CDKN1A		49
10	Czech (cs) P21		41

More...

The following table shows the language versions of the article with the highest Authors’ Interest.

Language versions of the article "P21" with the highest Authors Interest (number of authors). Only registered Wikipedia users were taken into account.

#	Language	AI award	Relative AI
1	English (en) P21		59
2	German (de) CDK-Inhibitor 1		28
3	Italian (it) P21		17
4	Polish (pl) P21		13
5	Spanish (es) P21		9
6	Japanese (ja) P21		9
7	Russian (ru) CDKN1A		9
8	Finnish (fi) P21 (proteiini)		7
9	Portuguese (pt) P21		7
10	French (fr) P21		6

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The following table shows the language versions of the article with the highest Authors’ Interest in the last month.

Language versions of the article "P21" with the highest AI in June 2025

#	Language	AI award	Relative AI
1	Czech (cs) P21		0
2	German (de) CDK-Inhibitor 1		0
3	English (en) P21		0
4	Spanish (es) P21		0
5	Finnish (fi) P21 (proteiini)		0
6	French (fr) P21		0
7	Indonesian (id) P21		0
8	Italian (it) P21		0
9	Japanese (ja) P21		0
10	Korean (ko) P21		0

More...

The following table shows the language versions of the article with the highest number of citations.

Language versions of the article "P21" with the highest Citation Index (CI)

#	Language	CI award	Relative CI
1	English (en) P21		192
2	Russian (ru) CDKN1A		63
3	Japanese (ja) P21		54
4	Spanish (es) P21		34
5	Czech (cs) P21		32
6	Ukrainian (uk) CDKN1A		25
7	French (fr) P21		18
8	Polish (pl) P21		16
9	German (de) CDK-Inhibitor 1		12
10	Italian (it) P21		12

More...

#	Language	Value
cs	Czech P21
de	German CDK-Inhibitor 1
en	English P21
es	Spanish P21
fi	Finnish P21 (proteiini)
fr	French P21
id	Indonesian P21
it	Italian P21
ja	Japanese P21
ko	Korean P21
nl	Dutch P21 (eiwit)
pl	Polish P21
pt	Portuguese P21
ru	Russian CDKN1A
uk	Ukrainian CDKN1A

Best Rank

Czech: #67197 06.2017

Global: #130248 04.2015

Best Rank

Czech: #26141 02.2018

Global: #86336 04.2013

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The WikiRank project is intended for automatic relative evaluation of the articles in the various language versions of Wikipedia. At the moment the service allows to compare over 44 million Wikipedia articles in 55 languages. Quality scores of articles are based on Wikipedia dumps from July, 2025. When calculating current popularity and AI of articles data from June 2025 was taken into account. For historical values of popularity and AI WikiRank used data from 2001 to 2025... More information