Unnamed Space Idle – Crew Rank Points Explanatory Guide + How to Spend

This is a small guide that explains how you should think about crew rank points and how to spend them.

Crew Rank Points Explained

By Someitoj

Upgrade Formula

Most crew upgrades are multipliers (This does not apply for Warp Speed upgrades). Let’s take a look at the ET’s first upgrade: Reactor Maintenance.

This would mean with 100 stat points you’d have “+ 1” and at a 1000 stat points “+ 10”. I’m calling this your Stat Bonus.

So how are these applied? 

Total Upgrade Bonus=1+Stat Bonus*Rank Points *Crew Skill

And this bonus is then added multiplicatively to the other bonuses.

Total=Other Bonuses*Total Upgrade Bonus

Now we get to the part that is actually relevant. Let’s line up the ET’s energy upgrades:

From top to bottom, I’ll call them Upgrade Bonus (UB): UB1, UB2 and UB3  plus the cornerstone (CS).

This gives:


How should you spend your points?

Well, here comes the actual reason I made this guidecause just putting points in the biggest multiplier does not yield the biggest return. 

How it scales with rank points

Note: if you don’t want to see math, you can just jump to the conclusion.

Let’s look at UB1 again:

  • Total Upgrade Bonus=1+Stat Bonus*Rank Points *Crew Skill

You have most control over the rank points. So let’s examine how to bonus scales when you put in more points. For this example I’ll always assume that Crew Skill is 1.

Rank PointsStat Bonus = 0.1Stat Bonus = 1Stat Bonus = 10

Quick question: 

Looking for each Stat Bonus, how large is the increase from 0 => 1 point and from 4 => 5 points?

  • SB = 0.1: 10% and ~7%
  • SB = 1: 100% and 20%
  • SB = 10: 1000% and  ~24%

Especially for the SB = 10, this is a huge drop off in gains. 

It is even more clear looking at the jump from 10 => 20.

  • SB = 0.1: 50% increase
  • SB = 1: ~90% increase
  • SB = 10: ~99% increase

What does this mean?

The first point you put into a skill does most of the work. But from then on, the actual Stat Bonus loses most relevance. Instead, you’re almost just multiplying by rank points.

When your stat bonus becomes large enough, doubling the amount of rank points is almost the same as getting a x2 multiplier on that stat. This is not true for when the stat bonus is low. 

  • Total=Others*UB1*UB2*UB3*CS

For our total, this means that, we can change the formula when the stat bonuses are large enough.

Total ≈ Others*(SB1*SB2*SB3)*(RP1*RP2*RP3)*CS

  • This assumes each upgrade has at least 1 rank point in it
  • Stat Bonus values for each upgrade are larger then 10
  • SB = Stat Bonus of that upgrade
  • RP = Rank points in that upgrade

In this equation, when you double the amount of rank points in any upgrade, your total stat doubles as a whole. 

For an upgrade with stat bonus x10, This can be interpreted as:

  • The upgrade multiplies your total stats by x10 for the first point
  • Then it multiplies your total stat by x1.9 every time you double the rank points spent on that upgrade


Take the following example:

  • Upgrade 1: gives x10 per point
  • Upgrade 2:  gives x1000 per point
  • Upgrade 3:  gives x10 per point

You might have thought previously that you should put all you points into upgrade 2 since it gave a much bigger bonus.

But the actual upgrade looks more like this:

  • Upgrade 1: gives x10 for the first point, then x1.9 every time you double the points 
  • Upgrade 2: gives x1000 for the first point, then x1.999 every time you double the points
  • Upgrade 3:  gives x10 for the first point, then x1.9 every time you double the points

So you should still spread your points around almost evenly, with just a bit more invested in Upgrade 2.

For bonuses smaller than 10, there is a notable difference (relevant for crew XP bonuses).

  • Upgrade X: gives x1.1 per point


  • Upgrade X: gives x1.1 for the first point, then slightly less than x1.1 each point.

So you can quite safely just spend most of your points in the one who is noticeably larger.


  • This can be applied to most bonuses in the game.
    If a bonus does not say “(multiplicative)”  and you can put multiple points into it (synth, warp,…) it scales like this and spreading points is useful.
  • It can be very useful, once you have enough rank points, to just ALWAYS put at least 1 or 2 rank points in each upgrade of a crewmember to get the initial first big bonus.
  • You mostly can’t go wrong by just spreading your points evenly amongst upgrades of the same type.

These 2 points in research give me a x8 and a x32 research bonus and I’m only missing like x1.1 power because of it.


A few graphs to demonstrate how it works. The graphs show the cumulative increase of the bonus past the first rank point you spend on it. 

  • The value on the y-axis is the total multiplier applied to your stat
  • The value on the x-axis are the amount of rank points spent on the upgrade
  • The value next the line is how large the stat bonus is.
    • Note: The picture below has a stat bonus of 0.19396,
      it just shows 1 + Stat Bonus

Total Upgrade Bonus=1+Stat Bonus*Rank Points *Crew Skill

The first graph looks at how it looks when you have a low stat bonus. This is relevant for bonuses like Crew XP increases.

  • For a stat bonus of 0.1 there is almost a straight line. A straight line would mean that every rank point increases the multiplier by the same amount. The slight downwards curvature means that each rank point increases the multiplier by slightly less than the previous rank point.
  • For 0.5 and 1 you can already see a pattern forming. The first few rank points increase the multiplier by a lot. For 1 you can see it only takes 4 rank points in total to double your multiplier. To double it another time however, you need to invest 31 points.

Now looking the next tier of bonuses, those between 2 and 11. These are relevant for the Synth Bonus.

You can see that for a bonus of 5 and 10 the multiplier already almost doubles at the second rank point.

And finally, the point I was trying to make, once your stat bonus goes above 10, the difference between where your points are spent becomes just so minimal that trying to optimise spending your points becomes meaningless. Just spread them evenly.

Research Example

In this example, my boosts are:

  • x37.5
  • x24.8
  • x137.25

I could’ve spent 6 more points on the x137.25 upgrade, that would be the same as x1.185 to my research.

By spending the way I did, i gained about x1.115 twice, netting me a total increase of  about x1.244

So, in this example, going from 25/25/30 to 25/25/36 would have given me x1.185

But going from 25/25/30 to 28/28/30 would gave me x1.244

It would be more optimal to have 29/28/29 here but I misclicked but don’t have anymore biosleeves.

Warp Speed Upgrades

You might’ve noticed the warp speed upgrades being slightly different. So how do they work ?

Let’s take a look at how the Charge speed works:

  • Tot = (1 + A)*B*C

Our crew bonus is located in A.

  •   (1+A) = (1 + others + crew)

You might notice this is actually not that different from what we encountered in the upgrade bonus:

  • Mult. Upgrade Bonus=1+Stat Bonus*Rank Points *Crew Skill

Except that all crew upgrades contribute to the same multiplier.

  • (1+A) = (1 + others + Research Bonus * RP + Xeno Bonus * RP)

The exact same logic thus also applies: there is a fall off for each upgrade. And both are contributing to the exact same pool. But since the warp speed upgrades are rather small, they behave more like the first graph.

Spending Rank Points

As far as spending your rank points goes in practice, technically your later rank points have a lower impact, but since each crew member with a warp speed upgrade only has one, the optimal usage of rank points is always just maxing out the charge speed upgrade.

In my example, I spent 50 rank points on both upgrades.

The Researcher ends up contributing equal to a  ~x1.12 multiplier
and the Xeno to a ~x8.66 multiplier.

But unlike the other upgrades I cannot say that spending X rank points is equal to an X multiplier since the impact of each upgrade is dependent on how large the other upgrades are.

A very simple demonstration of this concept:

Tot = 1 + y + x

  • for y= 0 ; x = 2; =>Tot = 3. 

x could then also be considered a x3 multiplier, since the total after x was added is 3 times larger than before.

  • for y= 9 ; x = 2; =>Tot = 12.

x would be considered a x1.2 multiplier despite adding the same number.

So in my example the Researcher upgrade ends up looking bad compared to the Xeno upgrade because the Xeno upgrade is so good. But if you would remove the Xeno upgrade, the total would be 12.71 and the Researcher upgrade would be like a ~x9.014 multiplier!

Is it worth spending 1 rank point for a boost?

If you are not focussing on warp, is it worth spending some rank points on the Researcher warp upgrade to speed it up in the background?

  • CASE 1: You have the Xeno

You have to spend 10 points into the speed upgrade anyway to access the other upgrades.
The researchers bonus is so small compared to the Xeno’s that it is not worth spending any points on it if you are focussing on the science.

  • CASE 2: You have NO Xeno

It can actually have a decent impact to spend a few rank points on it.

In my example: My Researcher gives + 0.22 speed per point, if I spend 1 point I am multiplying my speed by ~x1.157. If I let this run overnight, that is almost equal to getting an extra free 7th core every 6 cores I get!

Spending 2 rank points is like a ~x1.3 multiplier, giving me an extra free 4th core for each 3 cores I get. So yes, based on how long you let it run, it might be worth it.

Note: this might not really be useful for capital warp since it takes so long. But for the regular warp it actually might be useful.

Egor Opleuha
About Egor Opleuha 7128 Articles
Egor Opleuha, also known as Juzzzie, is the Editor-in-Chief of Gameplay Tips. He is a writer with more than 12 years of experience in writing and editing online content. His favorite game was and still is the third part of the legendary Heroes of Might and Magic saga. He prefers to spend all his free time playing retro games and new indie games.

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