| Document And Entity Information | May 08, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | May 08, 2023 |
| Entity Registrant Name | Vaxcyte, Inc. |
| Entity Central Index Key | 0001649094 |
| Entity Emerging Growth Company | false |
| Securities Act File Number | 01-39323 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 46-4233385 |
| Entity Address, Address Line One | 825 Industrial Road |
| Entity Address, Address Line Two | Suite 300 |
| Entity Address, City or Town | San Carlos |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94070 |
| City Area Code | 650 |
| Local Phone Number | 837-0111 |
| Entity Information, Former Legal or Registered Name | Not Applicable |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.001 par value per share |
| Trading Symbol | PCVX |
| Security Exchange Name | NASDAQ |
