Slipway — a free industry planner: what to build, where to build it, where to sell it

Hello fellow capsuleers,

I’ve built Slipway, a free industry planner. No sign-in needed to use it, no
subscription, ever.

It answers one question: what should I build, where should I build it, and where
should I sell it?
Pick a hub, get every T1 and T2 line ranked by what it actually
earns — not just the headline ISK/hour, but after the job fee in a real system, the
materials where you buy them, and the sale where you sell them.

What it does

:white_check_mark: Ranks every manufacturing line, invention line and reaction formula in the game
:white_check_mark: Buy hub, build system and sell region are three separate choices — because the
right hub to build in is often not the one with the best sell price
:white_check_mark: Caps every line by real traded volume, so it won’t tell you a thing that sells 3 a
week earns 5b/hour
:white_check_mark: Models your engineering complex: each rig applies to what CCP says it applies to,
scaled by the security of your system
:white_check_mark: Plan — give it capital, slots and a horizon, get a build queue and a shopping list
:white_check_mark: Trade — what’s worth hauling between two markets, ranked by profit per m³, and
it’ll fill a hold for you
:white_check_mark: Market browser across every tracked region and structure

Sign in with EVE (optional) and it gets personal:

:white_check_mark: Uses your blueprints’ real ME/TE, your skills and your hangars
:white_check_mark: Stock — what you can finish right now without buying anything
:white_check_mark: Jobs — every industry job across all your characters and your corporation in one
list, with local completion times, and it feeds your free slots back into Plan
:white_check_mark: Reads the order books of player structures you can dock at, which no public price
site can see

Sign-in is read-only and opt-in by tier: the default login never asks for corporation
anything. What each permission reads, and how to delete it all, is on the privacy
page.

Why I made it: Vorton Tuning System II is worth 214m built in Jita and 126m in
Amarr — even though Amarr has the better sell price and half the job fee — because
the hull costs 1.59× more there. No single number tells you where to build. I wanted
the tool that does the whole sum.

It’s new, and some of you run industry at a scale I don’t. If a number looks wrong,
I’d rather hear it than have it sit there:

• Item
• Hub / system
• What seems off

Every formula and assumption is written up at
How Slipway costs a build — the formulas, the data, and what is assumed — including what’s estimated rather than measured.

Fly safe o7
Karmikl

Not affiliated with or endorsed by CCP / Fenris Creations.

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Man the AI even named it, huh?

why hate?ai hate seems so forced

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I use AI quite a lot, and what I’m criticizing here isn’t the AI, but rather its unskilled, uncritical, and most of all lazy utilization.

I’ve heard software developers complain that, of late, they just do QC for the AI, but uh… You can’t just skip the QC part, which is clearly what OP has done here.

It’s only wrong by about 20%, so I can see how it could be easily overlooked by a blind person who also never checked the output even a single time.

Doing a little bit of napkin math here, it looks like this is probably calculating it as:

JobFee = EIV * SCI * (1+surchage+tax)
For an MTU in Jita that’s:

5177367 * .1707 * 1.0425 = 921,337

The correct calculation is actually:

EIV * SCI + EIV * (surchage+tax):

5177367 * .1707 + 5177367 * .0425 = 1,103,814

Now, this is an easily fixed bug, but it’s also an extremely obvious one that anyone would catch either at a glance, if they’re very familiar with prices, or during even the most casual of testing.

OP did not even queue a job to see if the values his calculator outputs matches the ingame values, he just called it good enough, slapped a Ko-Fi donation button on it, and shipped it.

I would go on, but I am pretty sure that I have already given this app more human mindshare than anyone else on the planet.

You’re right. Slipway was calculating the job fee incorrectly by applying the surcharge and tax to the SCI-adjusted value instead of applying them directly to EIV.

I’ve corrected the formula, verified the MTU example against the in-game job quote, and added a regression check so this calculation cannot quietly return. I’ve also credited Namdor on the site, with a link to his forum profile, for identifying the issue and providing a reproducible example.

This was a basic error that I should have caught before release. I’m now reviewing the rest of Slipway’s calculations against CCP documentation and data, the EVE University Wiki, and actual in-game results.

Thank you for calling it out. If anyone else finds something that looks wrong, please let me know—specific examples like this are especially helpful.

I mean. You probably pasted my comment into Claude Code or Codex, it did a bunch of thinking, read a bunch of unrelated files that have nothing to do with the price of tea in china, eventually said “Bug found… just a one liner, fixing now…” and then it went ahead and added the regression check on its own even though this isn’t a class of bug for which that makes sense because it’s a one line formula that exists in one place and never needs to be touched outside of the pricing formula changing.

Honestly, that’s not far off from how it went. What your math didn’t show was the scope: the same faulty fee logic was in eleven places across the codebase, and Jita was the mild case — in a quiet system it understated fees about 5×, and on invention’s thin index about 30×.

Your comment kicked off a broader audit against CCP’s published formula, the SDE, public references, and recorded in-game quotes. That turned up more issues: reaction-fee composition, invention EIV basis, copying-material scaling by licensed runs, skill eligibility, rounding, research limits. What’s confirmed against in-game quotes is fixed; what isn’t validated yet is marked pending in the app.

I kept the regression checks because they don’t ask the code to agree with itself — they pin independently calculated totals from actual in-game quotes, yours included, so a future “fix” can’t quietly bring any of it back.

Sharp delivery, but the app is substantially better because you raised it. Your point plus a bunch more are fixed and live.

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