How is the win chance calculated in Upgrader?

Divide the value of your item by the value of the target to get the break-even chance. An item worth 1,000 credits aimed at a 5,000-credit target is a 5x upgrade, so the break-even chance is 100 / 5 = 20%. A small balance margin is then subtracted, so the chance shown is slightly below the break-even figure.

Free browser game

Upgrader — the free online upgrade game

Q: Is Upgrader free to play?

Yes. Upgrader is free. There is nothing to buy, no credit packs, no premium currency and no paid unlocks. Credits exist only inside the game, cannot be purchased, and cannot be converted into anything outside it.

Q: Which multiplier should I pick?

It depends what you are playing for. Low multipliers of 1.5x to 2x land often and move you up the ladder slowly. High multipliers of 20x and above land rarely but jump several tiers at once. Neither is more efficient over time, because the same balance margin applies to every roll.

Q: What are the tiers in Upgrader?

There are five tiers: Standard, Refined, Elite, Prime and Apex. Each tier covers a value band, and the higher the tier you target, the larger the multiplier and the smaller the win chance. You can target any tier from any tier, including skipping several at once.

Upgrader is a free browser game built around one mechanic: you put in an item you already own, choose a higher-tier target, and take a single percentage-based roll for it. The win chance comes straight from the value gap between the two — aim twice as high and you are rolling near 50%, aim ten times as high and you are rolling near 10%.

Nothing here is bought and nothing is cashed out. This page explains the mechanic itself: how the multiplier sets your odds, what the five tiers are, and how the seeded roll lets you verify any result yourself.

Play free in your browser See the odds table

Price: Free — nothing to buy
Install: None — runs in browser
Per upgrade: 1 roll, win or lose
Results: Seeded & verifiable

What is an upgrader?

An upgrader is a one-shot exchange: one item in, one roll, one chance at something further up the ladder. Unlike a random drop, you choose the target yourself — and that choice is what sets your probability.

You pick the target

A random drop has a fixed table you cannot influence. An upgrade does not: you select the exact item you are aiming for, and the multiplier is calculated from its value against what you put in.

The multiplier is the odds

Multiplier = target value ÷ your item's value. Break-even chance = 100 ÷ multiplier. Aim at something ten times higher and you are taking a roll near 10% — not a hidden or arbitrary number.

It is all-or-nothing

There is no partial return. A successful upgrade replaces your item with the target; a failed one consumes it. That is the trade for skipping several tiers of grinding in a single step.

How a round works, step by step

Four steps from an empty slot to a result. Everything between step 2 and step 3 is plain arithmetic — no hidden weighting.

Open it in your browser

Nothing to install and nothing to download. Upgrader runs on desktop and mobile in any modern browser, and your starting items are handed to you — you never buy your way in.

Put in an item

Choose something from your inventory that you are willing to lose. Its in-game value is what the multiplier is measured against, so a Refined item and an Elite item aimed at the same target do not produce the same chance.

Choose the target and read your chance

Pick what you are upgrading toward. The multiplier and the exact win percentage are both shown before you commit — you should never be asked to roll on a number you have not seen.

Roll

One roll decides it. A win swaps the target into your inventory; a loss consumes what you put in. Either way the seed pair behind the roll stays on record so you can check it afterwards.

Multipliers and win chance

Break-even chance is 100 ÷ multiplier. A small balance margin is then subtracted, so the number you are offered sits just under it. Here is the full baseline.

Break-even figures before the balance margin. The chance actually shown in-game = break-even × (1 − margin). Credits are an in-game unit only; they cannot be bought and have no value outside the game.
Multiplier	Break-even chance	1,000 credits targets	What it feels like
1.5×	66.67%	1,500	Lands often, climbs slowly
2×	50.00%	2,000	A coin flip
3×	33.33%	3,000	Roughly 1 in 3
5×	20.00%	5,000	1 in 5
10×	10.00%	10,000	1 in 10 — a tier jump
20×	5.00%	20,000	1 in 20 — long odds
50×	2.00%	50,000	1 in 50 — rare
100×	1.00%	100,000	1 in 100 — Standard to Apex

Chance calculator

Enter any two values to see the multiplier and the chance you should expect.

Your item (credits)

Target (credits)

Multiplier5.00×

Break-even20.00%

After 5% margin19.00%

Why the chance is under break-even

The margin is not a fee taken out of a win — it is a thin slice off the wheel. If break-even says 20% and the margin is 5%, you are offered 19%. It applies to every roll, at every multiplier, win or lose.

It exists for one reason: without it, upgrading would inflate the economy and every tier would flatten out within a week. The practical consequence for you is that no multiplier is more efficient than any other — there is no pattern of small upgrades that beats one big one. Pick the multiplier that matches the item you actually want.

The five tiers

Every item sits in one of five tiers, and each tier covers a value band. You can aim from any tier at any tier — including skipping three at once, if you accept the multiplier that comes with it.

Standard

Where everyone starts. Cheap to lose, which makes it the right place to learn how the multiplier behaves.

100 – 999 credits

Refined

One clean 2× or 3× away from Standard. The first tier where a failed roll actually stings.

1,000 – 4,999

Elite

The middle of the ladder. Reachable from Standard in one 10× roll, or from Refined in a couple of safer ones.

5,000 – 24,999

Prime

Long odds from below. Most Prime items are reached from Elite rather than in a single jump from the bottom.

25,000 – 99,999

Apex

The top band. A 100× roll from Standard lands here about once in a hundred attempts — which is exactly what it sounds like.

100,000+

Verifiable rolls: check any result yourself

The outcome is committed to before you roll and can be recomputed by you after. You do not have to take anyone's word for it — you check the maths.

Commitment, before the roll

The server generates a random server seed and publishes only its SHA-256 hash. The hash is public and fixed; the seed behind it is not yet known to you, and cannot be changed afterwards without breaking the hash.

Your input

You set your own client seed, and a nonce counts up with each roll. Because you control part of the input, no outcome can be pre-computed for you specifically.

The result

The roll is HMAC-SHA256(server seed, client seed:nonce). The first bytes of that hex digest are read as an integer and mapped onto the 0–100 range. Same inputs, same output, every time — it is deterministic.

Reveal and audit

When you rotate your seed pair, the old server seed is revealed. Hash it yourself: if it matches the hash published in step 1, the seed was never swapped — and you can now recompute every roll made under it.

Verify in one command

# Node.js — recompute any past roll yourself
const crypto = require('crypto');

const serverSeed = 'REVEALED_SERVER_SEED';
const clientSeed = 'YOUR_CLIENT_SEED';
const nonce      = 1;

// 1. Does the revealed seed match the hash published before the roll?
console.log(crypto.createHash('sha256').update(serverSeed).digest('hex'));

// 2. Recompute the roll
const hmac = crypto.createHmac('sha256', serverSeed)
                     .update(`${clientSeed}:${nonce}`)
                     .digest('hex');

const roll = (parseInt(hmac.slice(0, 8), 16) % 10000) / 100;  // 0.00 – 99.99
console.log(roll, roll < yourChance ? 'WIN' : 'LOSS');

Free to play, and entirely self-contained

Worth stating plainly, because "upgrade game" covers a lot of very different things. Upgrader is a game and nothing else.

Nothing to buyNo credit packs, no premium currency, no paid unlocks, no subscription.

No walletThere is no payment form anywhere in the game, and nothing to pay in.

In-game onlyCredits and items exist inside Upgrader and stay there. They are not exchangeable.

No external tradingItems exist only inside Upgrader and cannot be moved to any other platform.

Frequently asked questions

The questions people actually search after "upgrader" — answered directly, in the first sentence.

What is an upgrader?

An upgrader is a game mechanic where you put in one item, select a higher-tier target, and take a single roll for it. Land inside your slice and the target replaces your item; miss and the item you put in is consumed. The win chance comes from the value gap between the two items.

How is the win chance calculated?

Divide the value of your item by the value of the target to get the break-even chance. An item worth 1,000 credits aimed at a 5,000-credit target is a 5× upgrade, so the break-even chance is 100 ÷ 5 = 20%. A small balance margin is then subtracted, so the chance shown is slightly below the break-even figure.

Is Upgrader free to play?

Yes. Upgrader is free. There is nothing to buy — no credit packs, no premium currency and no paid unlocks. Credits exist only inside the game, cannot be purchased, and cannot be converted into anything outside it.

Do I need to download or install anything?

No. Upgrader runs in the browser on desktop and mobile. There is no client to install, no launcher and no plugin.

How do I know the roll is actually random?

Every roll is seeded and verifiable. Before you roll, the server publishes a SHA-256 hash of its seed. You supply your own client seed. The outcome is HMAC-SHA256(server seed, client seed:nonce), mapped onto the 0–100 range. When the seed rotates, the server seed is revealed, so you can re-hash it, confirm it matches the published hash, and recompute every past roll yourself.

Which multiplier should I pick?

It depends what you are playing for. Low multipliers of 1.5×–2× land often and move you up the ladder slowly. High multipliers of 20× and above land rarely but jump several tiers at once. Neither is more efficient over time, because the same balance margin applies to every roll.

What happens when an upgrade fails?

The item you put in is consumed and you keep nothing from that roll. There is no partial refund and no consolation item. That is the trade-off for being able to reach a higher tier in one step instead of grinding to it.

What are the tiers?

There are five: Standard, Refined, Elite, Prime and Apex. Each covers a value band, and the higher the tier you target, the larger the multiplier and the smaller the win chance. You can target any tier from any tier, including skipping several at once.

About Upgrader

Upgrader is developed and operated by UPGRADE GROUP LIMITED, a private limited company registered in England and Wales. The registration below can be checked against the public Companies House register.

Legal name: UPGRADE GROUP LIMITED
Company number: 12983521 — view on the Companies House register
Company type: Private limited company
Incorporated: 29 October 2020
Registered office: Amelia House, Crescent Road, Worthing, England, BN11 1QR
Contact: support@upgrader.alphainstitute.edu.au