Provably fair on PackDraw: verify a draw

What provably fair means

The result of each open is tied to cryptographic values set before you commit, so neither the site nor the player can change it afterwards. The platform publishes a hash up front; after the open the hidden value is revealed and you recompute the hash to confirm the match. If it matches, the result was fixed in advance — provably.

The three components

• Server seed: generated by the platform and kept secret during the draw; its SHA-256 hash is published beforehand.
• Client seed: you control it and can change it at any time, so you add randomness the site cannot predict.
• Nonce: a counter that rises with each bet, so every draw is unique.

How to verify a draw

1. Before the draw, note the published hash of the server seed.
2. Open the pack; the result derives from server seed + client seed + nonce.
3. After the draw, the platform reveals the server seed.
4. Recompute the SHA-256 hash of the revealed seed and check it matches the one published earlier.
5. Run the published formula with the seeds and nonce and confirm it produces your result.

What provably fair does not do

It guarantees the integrity of a single result — not an edge for you. The published odds and the house edge do not change; over many opens the expected value stays negative. Provably fair is a transparency tool, not a way to win.

A step-by-step verification example

Imagine a simplified process with example values:

1. Before the draw the platform publishes the hash of the server seed, e.g. a3f9…c21 (SHA-256 of the secret seed).
2. You set your own client seed, e.g. my-random-42.
3. You open the pack; a nonce is used, e.g. 7.
4. After the draw the server seed is revealed, e.g. f8b1…09d.
5. You compute the SHA-256 of the revealed seed and check it matches a3f9…c21 from step 1.
6. You combine server seed + client seed + nonce, hash it and convert it with the published formula into the number that determined your result.

If the hash matches and the formula gives your drop, the result was fixed in advance and no one touched it. Most platforms offer a verification page or a guide with the exact formula.

Common misconceptions about provably fair

• "Provably fair = I win" — no; it only proves the honesty of the draw, not your advantage.
• "If I change the client seed I improve the odds" — no; you only change specific results, not the probabilities.
• "The hash can be reversed" — no; SHA-256 is a one-way function, which is why the pre-published hash is a proof.
• "A provably-fair badge is enough for me" — no; the proof only counts if you actually verify it.

What to check on a new site

• Is the server seed hash published before the draw?
• Can you set your own client seed?
• Is the server seed revealed after the draw, and is there a verification tool?
• Is the exact formula for turning the seeds into a result published?
• Are the domain, HTTPS and the official Steam sign-in correct?

Why provably fair exists

In the past a player simply had to trust that the site did not tilt the draw in its favour. Provably fair replaces that blind trust with a mathematical proof: thanks to the pre-published hash and the one-way SHA-256 function, the result cannot be changed after you commit without the check exposing it. It is a standard most serious pack platforms have adopted, because it shifts verifiability from "trust us" to "check it yourself".

Server seed vs. client seed in practice

Splitting into two seeds has a clear purpose. The platform keeps the server seed secret (publishing only its hash), so you cannot predict it. You hold the client seed and can change it, so the platform cannot predict it. Only their combination with the nonce produces the result — and because neither side knows the other's part in advance, no one can fix the drop beforehand. If you want to guarantee "fresh" randomness, change your client seed before a run of draws.