ER5Labs, the personal hub of Emad Rafiq
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I'm Emad Rafiq. This is my personal portfolio website where I keep, build and post my digital projects and works under ER5Labs, a home base for everything I create, control and collaborate on.
About
I am a Math and Finance student specializing in portfolio management and asset allocation, my core niche and passion. I actively manage a fund averaging 29.6% p.a. to date, backed by a strong foundation in logical thinking, data analysis, tax and accounting (including audits, filings and financial reporting).
Alongside finance, I design and build websites for personal and client projects, continually expanding my programming and web development toolkit.
Latest in the Playground
Bitcoin mining game
Added July 2026Proof of work against a genuine block. The 80-byte header comes live from the Bitcoin network and the hashing is real double SHA-256 running in a pool of Web Workers, so feeding it the real winning nonce reproduces that block's actual hash. The payout is the only part that is not real: the true target needs around 10²³ hashes, so you are scored against an easier practice target while the real target, the retarget maths and the profitability model sit alongside it.
What mining actually is
Mining is a guessing game. You take the block of transactions waiting to be recorded, add one changeable number to it called the nonce, and run the whole lot through a scrambler that turns any input into a 64 character code. Change the nonce by one and the code comes out completely different, with no way to predict it. So you just keep trying numbers.
You win when the code that comes out starts with enough zeros. That is the only rule. There is no cleverness available, only guessing quickly, which is why miners buy machines that guess trillions of times a second.
Everything below is the real thing: a real block off the Bitcoin network, the real scrambler, the real winning condition. The only change is that winning for real needs about a hundred thousand billion billion guesses, so you play against an easier goal.
The real block being hashed
You win here if the result starts with 0000
To win for real it would have to be smaller than …
How long should this take?
Every guess has the same tiny chance of winning, and guesses do not build on each other. So the curve below is your chance of having won by a given moment, at the speed you are actually going. The dashed line is the halfway point: you have a 50/50 chance of winning before it. Formally each nonce is an independent trial with p = 16−d, so the wait is geometric, and its continuous limit is exponential. That is why block arrivals across the network follow a Poisson process.
Start mining to model your own rate.
Why blocks always take ten minutes
As more machines join, blocks would come faster. So every two weeks the network counts how long the last 2016 blocks really took and moves the goalposts to bring the average back to ten minutes. Faster than ten and it gets harder, slower and it gets easier. next = current × (2016 × 600) / actual seconds, clamped to a factor of four either way so one strange fortnight cannot destabilise it.
…
Would a real machine make money?
You earn the same slice of the day's new coins as your slice of the world's guessing power, then pay for the electricity you burned. Change the numbers below to see when that is worth doing. The defaults are a top end machine on a normal home tariff. profit/day = (H ÷ Hnet) × 144 × 3.125 × price × (1 − fee) − kW × 24 × tariff
The header, the hashing, the target, the retarget maths and the market data are all real. The payout is not: no cryptocurrency is mined, earned or transferred to anyone, and nothing is submitted to any network.