As in StarCraft: Brood War, Warcraft III and many other RTS games, StarCraft II retains the ability to save and view replays with a number of new and interesting features. The file sizes are still relatively small and average about 100kb for a 15 minute game. Replays are saved and stored in a special folder called "StarCraft II" in the user's Documents folder. If you disconnect from Battle.net while watching a replay you will be able to continue watching the replay until you exit the replay, where you will have to reconnect.
The StarCraft II Replay system has a number of improvements and new features compared to Brood War replays. These are listed below.
Heart of the Swarm introduced new features like:
- Take command
- Watch with others
- Restart Replay - +
- Switch player names: First + and afterwards +
- Workers active
As you play through a replay, you can now jump back to any point in the replay that you have already seen and view it again. To go forward is not possible but Faster x8 (Speed) will help.
 Player Selection
You can see a human players selection. E. g. a selected Marine will show a dashed circle around it. If Red selects a unit the circle will be red. In general the circle is in the players colour and what commands are being issued.
 Player Camera
You can view a players First-Person view at any time to see exactly what they were doing at any point in time. Eache player gets a number. In a 1v1 between MC and MMA, 1 is assigned to MC and 2 is assigned to MMA for example. If you choose "Everything (E)", you can switch temporaliy into the vision of a specific player. By holdingwhen having a unit of one player selected, your vision will switch to that of the player until you release .
 Unit Following
You can lock the camera to any unit to follow it around the map. To do this select the unit and press+ .
 Replay Overlay
An overlay in the top left displays various information for every player as chosen by the viewer. These options are listed below.
- Closes the box. No stats are displayed on the left side. Does not effect stats in the middle.
- Shows Minerals, Gas and Supply of all players. A player sees exactly the same amount in the upper right corner. It's an important value, if you want to follow Day's rule "Keep your money low!".
- These values are calculated per minute. They show Minerals and Gas, which is harvested by a specific player. The amount of all harvesters is displayed, too. Note: There is a difference between active workers and harversters. E. g. player X has 70 haversters, but 20 are not mining. Active workers would be 50, not 70.
- Displays where resources are being spent, either on Economy, Technology or Army.
- All units on the battlefield will be displayed. A killed unit will be deleted and won't be displayed. At the start of every game only 6 workers per base are displayed.
- Units ost
- Displays number of lost units.
- Pro uction
- Displays all research, construction and production taking place.
- active Forces
- Displays Army units in terms of resource cost and total Supply stats. Changed name "Army Value" into "Active Forces" with patch 2.0.x.
- Displays average and current APM. Due to Game Speed issues, these are currently inaccurate.
- In a 1v1 game, both players’ resource rows are shown in the upper right at the same time.
- The main game UI can now be hidden/shown by pressing + .
- The ability to toggle between player unit colors and team unit colors when watching a replay or observing by pressing + .
- New bigger panels are now available when observing or viewing a replay of 1v1 games. These panels are large and are shown in the top center portion of the screen:
- Player Name Panel: Displays the players' name, team color, race, and supply count - + .
- Current Income: + .
- Army and Worker supply: + .
- Units and Workers killed: + .
- Current APM: + .
- If you've lost a key unit in a game, for example the blue player's Banshee, you may be able to find it by selecting a blue unit and finding it on the control group display. Just double click the control group the Banshee is in and the camera will focus on the units.