v3.26.1
Summary of significant accounting policies - AR and contract assets and allowance for uncollectible AR and contract assets (Details)
 12 Months Ended
Dec. 31, 2025
CNY (¥)
Dec. 31, 2025
USD ($)
Dec. 31, 2024
CNY (¥)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
CNY (¥)
Dec. 31, 2023
USD ($)
Dec. 31, 2025
USD ($)
Summary of significant accounting policies              
Allowance for doubtful accounts ¥ (192,376,932)   ¥ (24,172,284)   ¥ (9,266,619)   $ (27,509,535)
Accounts receivable and contract assets, net 3,145,975,681   2,029,550,471       449,868,539
Past-due accounts receivables 1,671,316,456   601,840,014       238,995,074
Provision for accounts receivable and contract assets              
Allowance for accounts receivable and contract assets, Beginning balance 24,172,284 $ 3,456,591 9,266,619   21,875,166    
(Reversal of) Provision for accounts receivable and contract assets (net of recovery) 242,719,252 34,708,391 35,732,133   12,233,743    
Charge-off for accounts receivable and contract assets (74,514,604) (10,655,447) (20,826,468)   (24,842,290)    
Allowance for doubtful accounts of accounts receivable and contract assets 192,376,932   24,172,284   9,266,619   27,509,535
Allowance for accounts receivable and contract assets, Ending balance 192,376,932 27,509,535 24,172,284 $ 3,456,591 9,266,619    
Recoveries of charge-off of accounts receivables and contract assets 1,674,306 239,423 876,116   244,196    
Loan facilitation service              
Summary of significant accounting policies              
Accounts receivable and contract assets, net 2,265,148,190   1,552,073,237       323,911,882
Post-origination service              
Summary of significant accounting policies              
Accounts receivable and contract assets, net 320,204,893   182,035,610       45,788,691
Financing income              
Summary of significant accounting policies              
Accounts receivable and contract assets, net 82,869,705   75,973,998       11,850,210
Guarantee income              
Summary of significant accounting policies              
Accounts receivable and contract assets, net 566,604,458   184,648,331       81,023,360
Credit losses              
Summary of significant accounting policies              
Allowance for doubtful accounts (192,376,932)   (24,172,284)       (27,509,535)
Provision for accounts receivable and contract assets              
Allowance for accounts receivable and contract assets, Beginning balance 24,172,284            
Allowance for doubtful accounts of accounts receivable and contract assets 192,376,932   24,172,284       27,509,535
Allowance for accounts receivable and contract assets, Ending balance 192,376,932 27,509,535 24,172,284        
Other revenue              
Summary of significant accounting policies              
Accounts receivable and contract assets, net 103,525,367   58,991,579       14,803,931
Loans facilitated in 2023              
Provision for accounts receivable and contract assets              
Gross charge-off recorded in accounts receivables and contract assets         11,940,878 $ 1,707,523  
Loans facilitated in 2024              
Provision for accounts receivable and contract assets              
Gross charge-off recorded in accounts receivables and contract assets     25,684,320 3,672,809      
Loans Facilitated In 2025              
Provision for accounts receivable and contract assets              
Gross charge-off recorded in accounts receivables and contract assets 38,563,712 5,514,537          
Not Past-Due              
Summary of significant accounting policies              
Past-due accounts receivables 1,618,951,313   572,387,815       231,506,958
1 - 30 Days              
Summary of significant accounting policies              
Past-due accounts receivables 21,521,859   26,871,502       3,077,584
30 - 60 Days              
Summary of significant accounting policies              
Past-due accounts receivables 17,425,324   2,580,697       2,491,789
Over 60 days              
Summary of significant accounting policies              
Past-due accounts receivables 13,417,960   0       1,918,743
Xiaoying Credit Loan              
Summary of significant accounting policies              
Accounts receivable net 1,491,308,368   524,981,846       213,254,260
Contract assets 1,551,472,053   1,445,702,560       221,857,553
Allowance for doubtful accounts              
Past-due accounts receivables 1,567,791,089           224,191,143
Provision for accounts receivable and contract assets              
Accounts Receivable, Allowance for Credit Loss, Beginning Balance 17,866,589 2,554,888 4,010,770        
Allowance for doubtful accounts receivable 76,482,721   17,866,589   4,010,770   10,936,883
Accounts receivable, Provision of accounts receivable (net of recovery) 133,130,736 19,037,442 34,674,923   13,063,863    
Charge-off for accounts receivable assets (74,514,604) (10,655,447) (20,819,104)   (24,406,436)    
Accounts Receivable, Allowance for Credit Loss, Ending Balance 76,482,721 10,936,883 17,866,589 2,554,888 4,010,770    
Contract assets, beginning balance 6,180,181 883,754 3,485,827   6,480,105    
Allowances for doubtful contract assets 115,564,104   6,180,181   3,485,827   16,525,447
Provision for contract assets (net of recovery) 109,383,923 15,641,693 2,694,354   (2,994,278)    
Charge-off for contract assets 0 0 0   0    
Contract assets, ending balance 115,564,104 16,525,447 6,180,181 883,754 3,485,827    
Allowance for accounts receivable and contract assets, Beginning balance         15,353,343    
Allowance for doubtful accounts of accounts receivable and contract assets              
Xiaoying Credit Loan | Loan facilitation service              
Summary of significant accounting policies              
Accounts receivable gross 1,020,377,108   287,995,740       145,911,985
Contract assets gross 1,244,771,082   1,264,077,497       177,999,897
Xiaoying Credit Loan | Post-origination service              
Summary of significant accounting policies              
Accounts receivable gross 144,057,260   33,776,512       20,599,914
Contract assets gross 176,147,633   148,259,098       25,188,777
Xiaoying Credit Loan | Financing income              
Summary of significant accounting policies              
Accounts receivable gross 82,869,705   75,514,367       11,850,210
Contract assets gross 0   459,631       0
Xiaoying Credit Loan | Guarantee income              
Summary of significant accounting policies              
Accounts receivable gross 320,487,016   145,561,816       45,829,034
Contract assets gross 246,117,442   39,086,515       35,194,326
Xiaoying Credit Loan | Credit losses              
Provision for accounts receivable and contract assets              
Accounts Receivable, Allowance for Credit Loss, Beginning Balance 17,866,589            
Allowance for doubtful accounts receivable 76,482,721   17,866,589       10,936,883
Accounts Receivable, Allowance for Credit Loss, Ending Balance 76,482,721 10,936,883 17,866,589        
Contract assets, beginning balance 6,180,181            
Allowances for doubtful contract assets 115,564,104   6,180,181       16,525,447
Contract assets, ending balance 115,564,104 16,525,447 6,180,181        
Xiaoying Credit Loan | Other revenue              
Summary of significant accounting policies              
Accounts receivable gross 0   0       0
Contract assets gross 0   0       0
Xiaoying Credit Loan | Not Past-Due              
Summary of significant accounting policies              
Past-due accounts receivables 1,538,110,113           219,946,820
Xiaoying Credit Loan | 1 - 30 Days              
Summary of significant accounting policies              
Past-due accounts receivables 9,235,273           1,320,626
Xiaoying Credit Loan | 30 - 60 Days              
Summary of significant accounting policies              
Past-due accounts receivables 12,776,048           1,826,951
Xiaoying Credit Loan | Over 60 days              
Summary of significant accounting policies              
Past-due accounts receivables 7,669,655           1,096,746
Other service              
Summary of significant accounting policies              
Accounts receivable gross     58,866,065        
Accounts receivable net 103,195,260           14,756,726
Past-due accounts receivables 103,525,367   58,991,579       14,803,931
Provision for accounts receivable and contract assets              
Accounts Receivable, Allowance for Credit Loss, Beginning Balance 125,514 17,949 1,757,267     0  
Allowance for doubtful accounts receivable 330,107   125,514   1,757,267   47,205
Accounts receivable, Provision of accounts receivable (net of recovery) 204,593 29,256 (1,631,753)   1,757,267    
Charge-off for accounts receivable assets 0 0 0     $ 0  
Accounts Receivable, Allowance for Credit Loss, Ending Balance 330,107 47,205 125,514 $ 17,949 1,757,267    
Other service | Loan facilitation service              
Summary of significant accounting policies              
Accounts receivable gross 0   0       0
Other service | Post-origination service              
Summary of significant accounting policies              
Accounts receivable gross 0   0       0
Other service | Financing income              
Summary of significant accounting policies              
Accounts receivable gross 0   0       0
Other service | Guarantee income              
Summary of significant accounting policies              
Accounts receivable gross 0   0       0
Other service | Credit losses              
Provision for accounts receivable and contract assets              
Accounts Receivable, Allowance for Credit Loss, Beginning Balance 125,514            
Allowance for doubtful accounts receivable 330,107   125,514       47,205
Accounts Receivable, Allowance for Credit Loss, Ending Balance 330,107 $ 47,205 125,514        
Other service | Other revenue              
Summary of significant accounting policies              
Accounts receivable gross 103,525,367   58,991,579       14,803,931
Other service | Not Past-Due              
Summary of significant accounting policies              
Past-due accounts receivables 80,841,200   38,166,429       11,560,138
Other service | 1 - 30 Days              
Summary of significant accounting policies              
Past-due accounts receivables 12,286,586   20,825,150       1,756,958
Other service | 30 - 60 Days              
Summary of significant accounting policies              
Past-due accounts receivables 4,649,276   0       664,838
Other service | Over 60 days              
Summary of significant accounting policies              
Past-due accounts receivables 5,748,305   0       $ 821,997
Other loans              
Summary of significant accounting policies              
Allowance for doubtful accounts              
Past-due accounts receivables     542,848,435        
Provision for accounts receivable and contract assets              
Accounts Receivable, Allowance for Credit Loss, Beginning Balance ¥ 0   12,755        
Allowance for doubtful accounts receivable     0   12,755    
Accounts receivable, Provision of accounts receivable (net of recovery)     (5,391)   409,477    
Charge-off for accounts receivable assets     (7,364)   (435,854)    
Accounts Receivable, Allowance for Credit Loss, Ending Balance     0   12,755    
Contract assets, beginning balance     0   2,586    
Allowances for doubtful contract assets         0    
Provision for contract assets (net of recovery)         (2,586)    
Charge-off for contract assets         0    
Contract assets, ending balance         0    
Allowance for accounts receivable and contract assets, Beginning balance         ¥ 39,132    
Allowance for doubtful accounts of accounts receivable and contract assets              
Other loans | Not Past-Due              
Summary of significant accounting policies              
Past-due accounts receivables     534,221,386        
Other loans | 1 - 30 Days              
Summary of significant accounting policies              
Past-due accounts receivables     6,046,352        
Other loans | 30 - 60 Days              
Summary of significant accounting policies              
Past-due accounts receivables     2,580,697        
Other loans | Over 60 days              
Summary of significant accounting policies              
Past-due accounts receivables     ¥ 0