Survival Log Items: Trade Value, Fuel and Spoilage

The short answer

Judge an item by the value you need from it, not by its price. A supply carries six of them: what it restores, what it weighs against that, what a shop charges, what a contact gives for it, what it burns for, and what it turns into when it spoils. The last two are where the surprises are: 47 items are worth at least twice as much to a contact as a shop charges, and is 960 fuel a dollar while most things burn for nothing at all.

Holds when: The item is in a shop or in your bag and you are deciding whether to take it.
What it costs: Everything costs the same two things in the end: the money in the prep window, and the weight it takes out of a trip afterwards.
Otherwise: If you are not sure what an item is for, its own row on the [supplies list](/supplies/) carries all six values at once, which is faster than judging it by the shelf.

What you are deciding Packing a bag A contact wants something The generator is empty It is about to spoil

Packing a bag

A trip is limited by weight, so the figure is Satiety per kilogram. Gecko leads at 333 and the bottom of the list is not worth the space. Where to scavenge has what each site holds; the supplies list sorts on the same figure.

A contact wants something

Send what they value rather than what you paid for. 47 items give a contact at least twice their shelf price, led by Rat (Dead) at 18 times, and 90 give back almost nothing. The phone has who wants which category.

The generator is empty

72 things burn and 66 of them can be found, including 34 the shops also stock, so searching reaches far more of the list than a shelf does even though about half of it is sold. is the one worth buying at 960 fuel a dollar; what it takes to keep the lights on has the whole budget and what each device draws.

It is about to spoil

A perishable does not vanish: 186 of the 202 items with a shelf life become Basic Fertilizer, which takes 30% off a crop’s grow time. Eating it late is the risk; letting it go is a transfer. Spoilage has how many days past the date each food is still safe, and how growing works has what the fertiliser is worth in the pot.

Open the supplies list Every item with all six values at once: what it restores, its weight, its price, its trade value, what it burns for and how it spoils.

The six values an item carries

What an item is worth, by the question you are asking of it.
The value	What it answers	How many items carry it
What it restores	Whether eating or using it helps now	286
Weight	Whether it earns its place in the bag	475
Price	What a shop charges in the prep window	445
Trade value	What a contact gives for it	453
Fuel	What it burns for in a generator	72
Shelf life	How long before it turns into something else	202

A Box of Saved Days — The same box of supplies is worth different amounts to a shop, a contact and a generator.

Price and trade value are two different numbers

A shop’s price and a contact’s trade value are not a fixed ratio: across the 443 items that carry both, it runs from Rat (Dead) at $1 for 18 back, which is 18 times over, down to Mysterious Envelope at $200 for 1.

The items a contact values most against their shelf price.
Item	Shop price	Trade value	Times over
Rat (Dead)	$1	18	18×
Gray Rat (Dead)	$1	18	18×
Black Rat (Dead)	$1	17	17×
Mouse	$1	12	12×
Mouse (Dead)	$1	12	12×
Paper Airplane	$1	10	10×
Gray Rat	$2	18	9×
Gas Canister	$15	120	8×

That is the phone’s arbitrage: what a trip brings back for nothing can be worth several times a shop’s price to somebody who wants it.

And the ones a contact barely values at all.
Item	Shop price	Trade value
Mysterious Envelope	$200	1
Workbench User Manual	$200	1
Over-Wrapped Gift Box	$200	1
Fruit Crate	$200	1
Medical Record Fragment: Outpatient	$200	1
Medical Record Fragment: Laboratory	$200	1

What a supply is an input to

21 items are used by a recipe, which is a value that never shows on the shelf.

The items the most recipes call for.
Item	Recipes that use it
Scrap Metal	69
Wire	36
Electronic Components	34
Waste Plastic	28
Broken Glass	25
Plastic Sheet	22
Wood Chips	18
Scrap Paper	16

What to craft has the bench itself and what each recipe returns.

Spoiling is one ladder, not a property of the food

The steps a perishable takes past its date, in the game's own effects.
Step	What it applies
1	Diarrhea, weight 5
2	Stomachache, weight 4
3	Vomiting, weight 3
4	Fever, weight 2
5	Poisoned, weight 1

Of the 202 items with a shelf life, 197 carry a ladder at all, and they share this one: 196 exactly, with 1 differing in its last step alone. So how badly a food can hurt you is not a property of the food; how long you have before it gets there is, and that is its shelf life.

What a spoiled item leaves behind.
Leaves behind	Items that leave it
Basic Fertilizer	186

What to do

Read the value you need. The shelf price answers one question only, and it is the one that stops mattering on day one.
Send a contact what they value, not what you paid for. 47 items are worth double or better to them.
Buy fuel by what it burns per dollar, not by what it costs: at 960. The other 35 that no shop stocks are the ones a shelf will never hand you, so the shop list is what to spend money on rather than the whole of what burns.
Pack by Satiety per kilogram. Gecko at 333 is worth four times what the bottom of the list is.
Let a perishable rot rather than eating it late. It becomes Basic Fertilizer and the ladder above is what eating it costs.

Quick reference

Values an item carries: six, of which the shelf price is the least useful.
Worth double to a contact: 47 items, up to 18 times.
Burns: 72 items, 37 of them sold; best bought is Diesel at 960 a dollar.
Shelf life: 202 items carry one, and 197 of those take the five-step ladder.
Rots into: Basic Fertilizer, from 186 of them.