| Document and Entity Information | Dec. 16, 2022 |
| Document And Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Dec. 16, 2022 |
| Entity Registrant Name | MariaDB plc |
| Entity Incorporation, State or Country Code | L2 |
| Entity File Number | 001-41571 |
| Entity Tax Identification Number | 00-0000000 |
| Entity Address, Address Line One | 699 Veterans Blvd |
| Entity Address, City or Town | Redwood City |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94063 |
| City Area Code | 855 |
| Local Phone Number | 562-7423 |
| Entity Information, Former Legal or Registered Name | Mangomill plc |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Current Fiscal Year End Date | --12-31 |
| Amendment Flag | false |
| Entity Central Index Key | 0001929589 |
| Former Address [Member] | |
| Document And Entity Information [Line Items] | |
| Entity Address, Address Line One | 590 Madison Avenue |
| Entity Address, Address Line Two | 21st Floor |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10022 |
| Ordinary Shares, nominal value $0.01 per share [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Ordinary Shares, nominal value $0.01 per share |
| Trading Symbol | MRDB |
| Security Exchange Name | NYSE |
| Warrants, each whole warrant exercisable for one Ordinary Share at an exercise price of $11.50 per share [Member] | |
| Document And Entity Information [Line Items] | |
| Title of 12(b) Security | Warrants, each whole warrant exercisable for one Ordinary Share at an exercise price of $11.50 per share |
| Trading Symbol | MRDBW |
| Security Exchange Name | NYSE |
