| Cover - USD ($) $ in Billions | 12 Months Ended | ||
| Jan. 31, 2020 | Mar. 20, 2020 | Jul. 31, 2019 | |
| Cover [Abstract] | |||
| Document Type | 10-K/A | ||
| Document Annual Report | true | ||
| Document Period End Date | Jan. 31, 2020 | ||
| Current Fiscal Year End Date | --01-31 | ||
| Document Transition Report | false | ||
| Entity File Number | 001-38464 | ||
| Entity Registrant Name | Smartsheet Inc. | ||
| Entity Incorporation, State or Country Code | WA | ||
| Entity Tax Identification Number | 20-2954357 | ||
| Entity Address, Address Line One | 10500 NE 8th Street, Suite 1300 | ||
| Entity Address, City or Town | Bellevue, | ||
| Entity Address, State or Province | WA | ||
| Entity Address, Postal Zip Code | 98004 | ||
| City Area Code | (844) | ||
| Local Phone Number | 324-2360 | ||
| Title of 12(b) Security | Class A common stock, no par value per share | ||
| Trading Symbol | SMAR | ||
| Security Exchange Name | NYSE | ||
| Entity Well-known Seasoned Issuer | No | ||
| Entity Voluntary Filers | No | ||
| Entity Current Reporting Status | Yes | ||
| Entity Interactive Data Current | Yes | ||
| Entity Filer Category | Large Accelerated Filer | ||
| Entity Small Business | false | ||
| Entity Emerging Growth Company | false | ||
| ICFR Auditor Attestation Flag | true | ||
| Entity Shell Company | false | ||
| Entity Public Float | $ 4.4 | ||
| Entity Common Stock, Shares Outstanding | 118,833,426 | ||
| Documents Incorporated by Reference | Certain sections of the registrant’s definitive proxy statement for its 2020 Annual Meeting of Shareholders (“Proxy Statement”), are incorporated herein by reference in Part II and Part III of this Annual Report on Form 10-K. The Proxy Statement will be filed with the Securities and Exchange Commission within 120 days of the registrant’s fiscal year ended January 31, 2020. | ||
| Amendment Description | Smartsheet Inc. (the “Company”) is filing this Amendment No. 1 to its annual report on Form 10-K for the fiscal year ended January 31, 2020, as filed with the Securities and Exchange Commission on March 31, 2020 (the “Original Form 10-K”), in order to file an updated Consent of PricewaterhouseCoopers LLP, Independent Registered Public Accounting Firm filed as Exhibit 23.1 and to correct the inadvertent omission of certain language in paragraph 4 of the certification of its Chief Executive Officer filed as Exhibit 31.1 and the certification of its Chief Financial Officer filed as Exhibit 31.2 to the Original Form 10-K.This Amendment No. 1 should be read in conjunction with the Original Form 10-K, which continues to speak as of the date of the Original Form 10-K. Other than the filing of the corrected exhibits mentioned above, this Amendment No. 1 does not modify or update the disclosures in the Original Form 10-K in any way. Accordingly, this Amendment No. 1 does not reflect events occurring after the filing of the Original Form 10-K or modify or update any related or other disclosures. | ||
| Document Fiscal Year Focus | 2020 | ||
| Amendment Flag | true | ||
| Document Fiscal Period Focus | FY | ||
| Entity Central Index Key | 0001366561 |
