| Document and Entity Information | 6 Months Ended |
| Jun. 30, 2023 | |
| Document Information [Line Items] | |
| Document Type | S-1/A |
| Amendment Flag | true |
| Amendment Description | Amendment No. 1 |
| Entity Registrant Name | KINTARA THERAPEUTICS, INC. |
| Entity Central Index Key | 0001498382 |
| Entity Small Business | true |
| Entity Filer Category | Non-accelerated Filer |
| Entity Emerging Growth Company | false |
| Entity Incorporation, State or Country Code | NV |
| Entity Tax Identification Number | 99-0360497 |
| Entity Address, Address Line One | 9920 Pacific Heights Blvd |
| Entity Address, Address Line Two | Suite 150 |
| Entity Address, City or Town | San Diego |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92121 |
| City Area Code | 858 |
| Local Phone Number | 350-4364 |
| Entity Primary SIC Number | 2834 |
| Business Contact [Member] | |
| Document Information [Line Items] | |
| Entity Address, Address Line One | 9920 Pacific Heights Blvd |
| Entity Address, Address Line Two | Suite 150 |
| Entity Address, City or Town | San Diego |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92121 |
| City Area Code | 858 |
| Local Phone Number | 350-4364 |
| Contact Personnel Name | Robert E. Hoffman |
