How many followers does Captain Mark Kelly have on X?

Captain Mark Kelly (@CaptMarkKelly) has 525,913 followers on X (Twitter). The count is refreshed continuously from public data.

When did Captain Mark Kelly join X, and how old is the account?

Captain Mark Kelly joined X in August 2009. The @CaptMarkKelly account is 17 years old. Searches for Captain Mark Kelly age often mean a personal age, which we do not publish. The figure here is the account age only.

How many posts has Captain Mark Kelly published?

Captain Mark Kelly has published 6,890 posts on X. That is about 1.1 posts per day over the life of the account.

Is Captain Mark Kelly verified on X?

Yes. Captain Mark Kelly carries a Government verification on X.

Captain Mark Kelly Twitter (X) Account Stats

@CaptMarkKelly

English ScienceGovernmentTier A

View on X

#147 in Science

Tucson, ArizonaAccount age: 17 years (joined August 2009)x.com

Captain Mark Kelly Twitter (X) stats, updated continuously. @CaptMarkKelly has 525,913 followers and 6,890 posts on X. Account age: 17 years (joined August 2009).

Followers

526K

Growth (7d)

Following

1.5K

Influence

1.0K

Posts

6.9K~1.1/day

Likes given

342

Media posts

2.6K

Follower ratio

355:1

Engagement

Top quarter for its size

Per follower

0.285%

of 526K followers

Per impression

7.04%

21K views on a typical post

Reach

4.05%

of its followers see a post

Typical post

1.5K

interactions (median)

Saved

0.049%

10 bookmarks on a typical post

Posting rate

1.93/day

active 87% of days

Peak time

21:00 UTC

Wednesday

A typical post picks up 1.5K interactions against 526K followers, an engagement rate of 0.285%. Measured over 46 original posts, its engagement rate beats 84% of 3,758 tracked accounts of a similar size. Comparing inside a size band matters here: engagement rate falls as accounts grow, so a raw rate would mostly just re-measure the follower count. Posts are seen about 21K times each, and 7.04% of those impressions turn into an interaction. That is about 4.05% of the follower count, which is the gap between an audience on paper and an audience in a timeline.

Measured over 46 original posts from a 30-day window, last computed on August 27, 2026. Recurring tags: #oh07, #va01.

Full engagement report

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Follower growth

Not enough history yet - growth is tracked from first discovery.

Bio

Navy combat veteran and retired NASA astronaut. Husband to @GabbyGiffords. United States Senator for the great state of Arizona.

Notable followers

The biggest accounts in our directory following @CaptMarkKelly.

The Daily Show8.7M Jessica Alba6.8M Chelsea Handler6.7M Matt Gaetz3.5M Lawrence O'Donnell2.9M

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Captain Mark Kelly on Twitter (X) - frequently asked questions

How many followers does Captain Mark Kelly have on X?: Captain Mark Kelly (@CaptMarkKelly) has 525,913 followers on X (Twitter). The count is refreshed continuously from public data.
When did Captain Mark Kelly join X, and how old is the account?: Captain Mark Kelly joined X in August 2009. The @CaptMarkKelly account is 17 years old. Searches for Captain Mark Kelly age often mean a personal age, which we do not publish. The figure here is the account age only.
How many posts has Captain Mark Kelly published?: Captain Mark Kelly has published 6,890 posts on X. That is about 1.1 posts per day over the life of the account.
Is Captain Mark Kelly verified on X?: Yes. Captain Mark Kelly carries a Government verification on X.
What does Captain Mark Kelly post about?: Captain Mark Kelly is classified under Science in our directory. Bio: "Navy combat veteran and retired NASA astronaut. Husband to @GabbyGiffords. United States Senator for the great state of Arizona.".