Why does it say the inventory is not available?

Steam only shares an inventory that is set to Public. The owner can change it under Steam - Edit Profile - Privacy Settings - Inventory. It can also mean the account holds no Rust skins.

How are the skins priced?

At the same canonical price the whole wiki uses: Steam's lowest sell order for the skin, or the highest buy order when nothing is listed. Skins with no Steam market listing show as unpriced and count as $0.

How fresh is the data?

A fresh read from Steam is kept for 24 hours; the Reload link forces a new read. Prices are always today's.

Is the Rust inventory value accurate?

It is what the inventory is worth on the Steam Community Market right now, which is what almost everyone means by inventory value. What you would actually receive in a sale is lower: Steam takes roughly a 15% fee on every market sale, and thinly traded skins can take a long time to sell at the listed price.

Do I need to log in or send a trade offer?

No. Everything is read from public Steam data, so there is no login, no API key and no trade URL - which is also why you can check anyone's inventory, not just your own. It is free with no cap.

Can I see what an inventory looked like before?

Yes. Every day an inventory is checked, a snapshot of its items and that day's prices is saved; pick a date on the result page to view it. The value chart also has longer ranges and a custom date range.

Can I use this from code?

Yes - the rust.wiki API exposes the same lookup at /api/v1/inventory/{steamid} with an API key.

Rust 库存价值计算器

粘贴 Steam 个人资料链接、自定义 URL 名称或 SteamID64，即可按本百科其他部分使用的同一套 Steam 实时价格，为该账号的 Rust 皮肤估值。库存必须在 Steam 上设为公开。免费，无需登录，无需交易报价。

指南： Steam 交易限制：为什么无法交易以及如何查询

已查询的库存

58,806

已查询的总价值

$18,891,961.56

最有价值的 Rust 库存

第 964 页，共 2941 页

#	玩家	物品	价值
19261	Joshey Monster	57	$123.37
19262	MR.PATATE	52	$123.37
19263	monsters	25	$123.35
19264	MASKARR	75	$123.33
19265	Fat and TURNT	51	$123.32
19266	Triple	70	$123.31
19267	EpsteinPeek	4	$123.29
19268	Dilly	19	$123.27
19269	JESGUA	43	$123.26
19270	NightHawk	77	$123.24
19271	bushw00k	38	$123.24
19272	Gryden	39	$123.22
19273	ALEJANDRO IV EL CONQUISTADOR	62	$123.22
19274	no name	87	$123.20
19275	Tax	80	$123.19
19276	FROGGO	86	$123.17
19277	DM Bot # 6318	28	$123.17
19278	alish	29	$123.17
19279	DM Bot # 8735	13	$123.13
19280	rescori	77	$123.10