FT Vest Laddered U.S. Equity Equal Weight Buffer ETF N-1A Cover |
May 31, 2026 |
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| Prospectus [Line Items] | |
| Document Type | 485BPOS |
| Amendment Flag | false |
| Registrant Name | First Trust Exchange-Traded Fund VIII |
| Entity Central Index Key | 0001667919 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | May 31, 2026 |
| Prospectus Date | Oct. 01, 2026 |
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- References Reference 1: http://www.xbrl.org/2003/role/presentationRef
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