SANTA CLARA, Calif. -- Upon hiring a new coach in Kyle Shanahan and general manager in John Lynch, the San Francisco 49ers were basically guaranteed to begin a massive makeover of their roster. The only question was just how big that makeover would be?

Now that free agency, the NFL draft and undrafted free agency are over, we have a chance to put into context just how big those changes were. As of this week, the Niners' 90-man roster features 50 players that have been drafted or signed since Shanahan and Lynch took over. That's good for a 55.5 percent turnover of the roster.

To be sure, Lynch and Shanahan's work is far from over, but here's a look at who the Niners have added this offseason as well as how they've positioned themselves for 2018:

Salary-cap space: $72,397,252 (only includes top 51 contracts)

2018 draft picks: Nine total -- First round (own), second round (own), second round (from New Orleans), third round (own), third round (from Chicago), fifth round (own), sixth round (own), seventh round (own), seventh round (from Kansas City).

Unrestricted free agents added (18): QB Matt Barkley, C Tim Barnes, WR DeAndre Carter, LB Brock Coyle, OL Brandon Fusco, WR Pierre Garcon, WR Marquise Goodwin, K Robbie Gould, RB Tim Hightower, QB Brian Hoyer, S Don Jones, FB Kyle Juszczyk, DT Earl Mitchell, TE Logan Paulsen, WR Aldrick Robinson, LB Malcolm Smith, LB Dekoda Watson, CB K'Waun Williams.

Restricted free agents added (1): OL Garry Gilliam (from Seattle)

Acquired via trade (2): RB Kapri Bibbs (from Denver), OL Jeremy Zuttah (from Baltimore).

Drafted rookies (10): QB C.J. Beathard, CB Adrian Colbert, LB Reuben Foster, DT D.J. Jones, TE George Kittle, DL Pita Taumoepenu, WR Trent Taylor, DL Solomon Thomas, RB Joe Williams, DB Ahkello Witherspoon.

Undrafted rookies (19): WR Victor Bolden, WR Kendrick Bourne, RB Matt Breida, OL John Flynn, CB Zach Franklin, LB Jimmie Gilbert, S Malik Golden, OL Evan Goodman, TE Cole Hikutini, S Chanceller James, S Lorenzo Jerome, WR BJ Johnson III, OL Richard Levy, OL Erik Magnuson, FB Tyler McCloskey, QB Nick Mullens, LB Donavin Newsom, DL Noble Nwachukwu, OL Darrell Williams Jr.