| Cover | Nov. 15, 2021 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Nov. 15, 2021 |
| Entity File Number | 001-39040 |
| Entity Registrant Name | AST SpaceMobile, Inc. |
| Entity Central Index Key | 0001780312 |
| Entity Tax Identification Number | 84-2027232 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | Midland Intl. Air & Space Port |
| Entity Address, Address Line Two | 2901 Enterprise Lane |
| Entity Address, City or Town | Midland |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 79706 |
| City Area Code | (432) |
| Local Phone Number | 276-3966 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
| Entity Information, Former Legal or Registered Name | Not Applicable |
| Class A common stock, par value $0.0001 per share | |
| Title of 12(b) Security | Class A common stock, par value $0.0001 per share |
| Trading Symbol | ASTS |
| Security Exchange Name | NASDAQ |
| Warrants exercisable for one share of Class A common stock at an exercise price of $11.50 | |
| Title of 12(b) Security | Warrants exercisable for one share of Class A common stock at an exercise price of $11.50 |
| Trading Symbol | ASTSW |
| Security Exchange Name | NASDAQ |
