These aren't official (X doesn't publish exact numbers), but they're widely repeated in 2025 growth discussions:

- 1 bookmark ≈ 5–10 likes (the 5× figure you mentioned is the most common shorthand, with some saying 10× for very high-signal content)
- 1 reply ≈ 5–27× a like (replies are usually the strongest)
- 1 repost/retweet ≈ 15–20× a like

One recent breakdown even put bookmarks at a 5× multiplier compared to likes as the "highest value signal" for quality content.