Dxter's Deep Space Fleet Battle Calculator - Help Page


This is a tool to calculate the outcome of a battle in the game Deep Space Fleet. Select the ship types for the desired slots and specify the amount of each type. The attacking fleet is at the top. Specify all other tech, commander, and fs settings etc that apply. Leaving something out or misspecifying something can often result in large differences from the game result. To run the battle click the "Attack" button at the lower left.


The remaining ship counts will be shown in green and the dead ship counts in red. The total damage done to a side and the number of rounds will be shown to the right. For flagships the armor left and armor lost will be shown in green and red respectively.


In the output for a non NPC fleet there is an RBT number. RBT stands for Relative Build Time. This is probably the most important measure of a successful battle as it tells you relatively how long it will take to rebuild the killed ships. This number will not correspond exactly to the seconds it takes to rebuild your ships but a smaller RBT should mean that you can rebuild the ships faster. If white/event ships are killed the time used is twice that of aces.

Critical Damage

Critical Damage occurs randomly according to the Critical Chance percent. The calc implements this but it will almost always necessarily be a bit different than the server result due to randomness. Imagine the server flips a coin 20 times and you flip a coin 20 times. What are the chances that you will both flip heads or tails the same way each time? It's nil or more precicely 9-13.

What are Presets?

This is a way to save all the values in the form for later use. Say you are trying to optimize a wormhole 10 attack but you don't want to type the wormhole ships in every time. Then you can set up the wormhole ships for a sortie and click Presets->"Save Current". Give the preset a name and it will be stored in your browser cookie. Then the name you gave it will be in the presets list and you can select it to fill out the values for wormhole 10.

What is the NPC button?

This is for wormholes and mines. On defense put the NPC ships for a single wave/sortie and the calc with run 8 sorties using these same ships against the attackers.

Commander Skills

Under slot 4 you can set the ship skill levels for your commander. Click on a slot to set the ship type and level for the commander. To clear a slot, select any ship and set the level to zero.

FS Device

Set the installed flagship device and it's level. To clear the device, select any device and set the level to zero.

Update attacker

This is mainly for testing multi-sortie attacks on wormholes and mines. It allows you to update the attacking ships while leaving the defense unchanged.

Update defense

This is a feature to help you plan a multi-fleet attack on a large defense. It will update the ship counts on defense with what is left after the battle is over.

Effect of updating on flagships and turrets

Using Update attacker or Update defense will update the remaining flagship armor if any. In the rare case you want to update the ship counts but want to start with fresh flagship reset the flashship merge level. The analogous situation is true for turrets also.

What is "New window"?

If you click this the results of an attack will be opened in a new window. This may be useful if you want to search for various optimal ships but don't want to lose the results of previous tests.

How do you know what the defender has in PvP?

Well, this is an unfortunate aspect of the game. Since you only get an overall count of each ship type (based on tonnage) but don't know how they are distributed in slots it makes it very hard to plan an accurate battle. As you become familiar with an opponent though you can figure out how they tend to distribute ships and what class of ships they have, elite vs ace etc. The ship class can usually be easily determined by the tonnage vs might. Also, if you have reconnaissance 9 you can see the tech levels so you can tell if they can build elites or aces based on techs. Another option is to send a recon attack, just enough to see what the fleet is. If you don't know the slots, you can try different likely combinations and pick an attack fleet or fleets that seems to cover all of them the best.