| Document and Entity Information Document | Jan. 14, 2020 |
| Entity Information [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jan. 14, 2020 |
| Entity Registrant Name | MASIMO CORP |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-33642 |
| Entity Tax Identification Number | 33-0368882 |
| Entity Address, Address Line One | 52 Discovery |
| Entity Address, City or Town | Irvine |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92618 |
| City Area Code | (949) |
| Local Phone Number | 297-7000 |
| 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 |
| Trading Symbol | MASI |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000937556 |
| Amendment Flag | false |
