January

Jan. 4, 2021 ~ Jan. 10, 2021
Jan. 11, 2021 ~ Jan. 17, 2021
Jan. 18, 2021 ~ Jan. 24, 2021
Jan. 25, 2021 ~ Jan. 31, 2021

March

Mar. 1, 2021 ~ Mar. 7, 2021
Mar. 8, 2021 ~ Mar. 14, 2021
Mar. 15, 2021 ~ Mar. 21, 2021
Mar. 22, 2021 ~ Mar. 28, 2021
Mar. 29, 2021 ~ Apr. 4, 2021

February

Feb. 1, 2021 ~ Feb. 7, 2021
Feb. 8, 2021 ~ Feb. 14, 2021
Feb. 15, 2021 ~ Feb. 21, 2021
Feb. 22, 2021 ~ Feb. 28, 2021

April

Apr. 5, 2021 ~ Apr. 11, 2021
Apr. 12, 2021 ~ Apr. 18, 2021
Apr. 19, 2021 ~ Apr. 25, 2021
Apr. 26, 2021 ~ May 2, 2021

May

May 3, 2021 ~ May 9, 2021
May 10, 2021 ~ May 16, 2021
May 17, 2021 ~ May 23, 2021
Half-Year Manga Sales Ranking 2021
May 24, 2021 ~ May 30, 2021
May 31, 2021 ~ June 6, 2021

June

Jun. 7, 2021 ~ Jun. 13, 2021
Jun. 14, 2021 ~ Jun. 20, 2021
Jun. 21, 2021 ~ Jun. 27, 2021
Jun. 28, 2021 ~ Jul. 4, 2021

July

Jul. 5, 2021 ~ Jul. 11, 2021
Jul. 12, 2021 ~ Jul. 18, 2021
Jul. 19, 2021 ~ Jul. 25, 2021
Jul. 26, 2021 ~ Aug.1, 2021

August

Aug. 2, 2021 ~ Aug. 8, 2021
Aug. 9, 2021 ~ Aug. 15, 2021
Aug. 16, 2021 ~ Aug. 22, 2021
Aug. 23, 2021 ~ Aug. 29, 2021
Aug. 30, 2021 ~ Sep. 5, 2021

September

Sep. 6, 2021 ~ Sep. 12, 2021

January

Jan. 4, 2021 to Jan. 10, 2021
Jan. 11, 2021 to Jan. 17, 2021
Jan. 18, 2021 to Jan. 24, 2021
Jan. 25, 2021 to Jan. 31, 2021

February

Feb. 1, 2021 to Feb. 7, 2021
Feb. 8, 2021 to Feb. 14, 2021
Feb. 15, 2021 to Feb. 21, 2021
Feb. 22, 2021 to Feb. 28, 2021

March

Mar. 1, 2021 to Mar. 7, 2021
Mar. 8, 2021 to Mar. 14, 2021
Mar. 15, 2021 to Mar. 21, 2021
Mar. 22, 2021 to Mar. 28, 2021
Mar. 29, 2021 to Apr. 4, 2021

April

Apr. 5, 2021 to Apr. 11, 2021
Apr. 12, 2021 to Apr. 18, 2021
Apr. 19, 2021 to Apr. 25, 2021
Apr. 26, 2021 to May 2, 2021

May

May 3, 2021 to May 9, 2021
May 10, 2021 to May 16, 2021
May 17, 2021 to May 23, 2021
May 24, 2021 to May 30, 2021
May 31, 2021 to Jun. 6, 2021

June

Jun. 7, 2021 to Jun. 13, 2021
Jun. 14, 2021 to Jun. 20, 2021
Jun. 21, 2021 to Jun. 27, 2021
Jun. 28, 2021 to Jul. 4, 2021

July

Jul. 5, 2021 to Jul. 11, 2021
Jul. 12, 2021 to Jul. 18, 2021
Jul. 19, 2021 to Jul. 25, 2021
Jul. 26, 2021 to Aug. 1, 2021

August

Aug. 2, 2021 to Aug. 8, 2021
Aug. 9, 2021 to Aug. 15, 2021
Aug. 16, 2021 to Aug. 22, 2021
Aug. 23, 2021 to Aug. 29, 2021
Aug. 30, 2021 to Sep. 5, 2021

September

Sep. 6, 2021 to Sep. 12, 2021

Best viewed here

Note that all sales are for titles or releases that made onto the Top 30 Oricon Manga sales charts.