| Document and Entity Information | Dec. 03, 2019 |
| Cover [Abstract] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001627475 |
| Document Type | 8-K |
| Document Period End Date | Dec. 3, 2019 |
| Entity Registrant Name | UPWORK INC. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-38678 |
| Entity Tax Identification Number | 46-4337682 |
| Entity Address, Address Line One | 2625 Augustine Drive |
| Entity Address, Address Line Two | Suite 601 |
| Entity Address, City or Town | Santa Clara |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 95054 |
| City Area Code | (650) |
| Local Phone Number | 316-7500 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, $0.0001 par value per share |
| Trading Symbol | UPWK |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
