TRADING BASICS

Shares & options, in plain words.

How buying a share actually works, what a call and a put really are, and the costs most backtests hide.

Shares, without the mystique

The building block everything else prices off.

What a share is

A share is a small slice of ownership in a company — buy one and you own that fraction, no more, no less. The price you see quoted isn't set by any authority; it's simply the last price two people agreed to trade at. Every tick up or down is supply meeting demand: more buyers than sellers at a price pushes it up, more sellers than buyers pushes it down. There's no hidden formula underneath — just the running record of what people were willing to pay, one trade at a time.

Long and short

Going long is the familiar trade: buy low, sell high, and you profit if the price rises. Going short runs the sequence backwards — you borrow shares you don't own, sell them at today's price, and hope to buy them back cheaper later; you profit when the price falls, and you're on the hook if it doesn't. Quantradin's equities backtests never fill on the bar a signal fires. Long or short, the entry happens at the next day's open — no same-bar fills, no look-ahead, just the first honest price you could actually have traded at.

Stops

A stop is a standing order that exits your position automatically once price crosses a level you set — it caps how much a single bad trade can cost you, without you watching the screen all day. In a backtest, a stop is easy to fake: draw the line, count the win, move on. Quantradin doesn't. A stop only counts as a real exit if the held-to-exit path underneath it also survives to that price — otherwise you're crediting a fill a thin or gapping name might never have given you. That gap is what we call the stop-fillability mirage.

Why daily bars

Minute charts feel more precise, but precision isn't the same as clarity — zoom in far enough and you're mostly staring at noise, reacting to wiggles that mean nothing by the close. A daily bar forces one honest decision a day: given everything that happened since yesterday's close, do you act or not? That discipline is easier to learn from and harder to fool yourself with. It's also how Quantradin grades a strategy by default — signal to fill to verdict, one daily bar at a time. When you do want finer resolution, equity backtests can run on real exchange 1-minute bars instead — same honesty rules, just a closer look.

OPTIONS

Options, priced honestly

Options add leverage — and costs most backtests hide.

Calls and puts

An option is a contract, not a share. A call gives you the right — never the obligation — to buy 100 shares at a fixed price, the strike, on or before a set date, the expiry. A put gives you the right to sell 100 shares on the same terms. You can let either expire worthless if the trade doesn't go your way; the most you lose is what you paid for it. That asymmetry — capped downside, buying the right instead of the shares outright — is the whole appeal, and the whole reason it's priced differently from a share.

Strike, DTE, ITM/OTM

The strike is the fixed price written into the contract — what you'd pay (call) or receive (put) for the shares if you exercised. DTE is days to expiry — how much runway the contract has left before it's worthless or exercised. In-the-money (ITM) means the strike is already favorable versus the current price; out-of-the-money (OTM) means it isn't, yet. These aren't just vocabulary — they're two dials in the Quantradin builder: target-DTE picks how much time you buy, and ITM% picks how far in, or out of, the money you start.

Premium and theta

Premium is the price of the contract — what you actually pay to hold the right a call or put gives you. Part of that price is time value, and time value decays every single day, a drag traders call theta. That means an option isn't a bet only on direction — it's a bet on direction happening fast enough. Hold a call through a week where the stock goes nowhere, and you can still lose money, because the clock, not the price, is quietly working against you the whole time.

The spread is a real cost

Every option trade has two prices: what you'd pay to buy right now, the ask, and what you'd get to sell right now, the bid. A round trip through that spread — buy at the ask, sell at the bid — costs real money before the underlying moves a cent: roughly 5% on a liquid name, and materially more on anything thin. Most backtests skip this and fill at the friendly midpoint, which flatters every result. Quantradin doesn't — every backtest trade fills at the ask to buy and the bid to sell, never the mid, which is exactly why our numbers look worse and are more real.

Liquidity

An option chain is only as good as the people willing to trade it. A thin chain — few contracts changing hands — means the price you see may not be a price you can actually get; sometimes there's no real fill available at all. Most backtests wave this away and assume every signal fills. Quantradin counts a signal it can't fill as a skip instead of quietly dropping it, and shows the fillable fraction alongside the results. A strategy that only works because you pretended every trade would fill isn't a strategy — it's a spreadsheet trick.

HONESTY

The honest engine, in plain words

How Quantradin grades a strategy — and where you stay in control.

Try it free, no login

You can run one honest backtest without signing up. On the home page, build a strategy in the cockpit or paste a strategy's spec — the plain JSON that describes it — into the Spec panel, and press run. It's the same engine and the same honesty rules the paid product uses, not a watered-down demo: a real verdict, real fills, real costs. The only limit on the free run is how wide a slice of the market it will scan, so nobody grades the whole universe for free — the honesty of the result is never dialed back.

Minute bars, when you want them

By default Quantradin grades on daily bars — one honest decision a day. When you want a closer look, a shares strategy can run on real exchange 1-minute bars instead (this finer resolution is for shares only, not options). The no-look-ahead rule holds exactly as it does on daily bars: a signal on one minute fills at the next minute's open, never the same minute it fired. You get more detail without buying yourself a peek at a price you couldn't actually have traded.

Live-only safety tools

Some tools — a stop-loss, a take-profit cap, a profit-lock that ratchets your floor up as a trade wins — only run once a bot is deployed and trading. They never touch the backtest grade. Take-profit is kept out of every verdict on purpose: capping winners makes a backtest look smoother and steadier than the strategy actually earned, so grading with it would flatter a curve that didn't deserve it. You can still switch these on for a live bot — they protect real positions without ever inflating the score you were shown.

Live, shadow, shelf — you decide

When you deploy a bot, you pick its mode: live, shadow, or shelf. The engine gives its own read — LIVE, SHADOW, or SHELF — but that read is advice, not a gate. You choose. Even a bot the engine would shelf can go live if you want to watch it trade for yourself. We never tell you a strategy "doesn't work" or lock it away; the honesty lives in the numbers we show you — no look-ahead, real fills — not in overriding your call.

Real quotes, never the mid

When a real, measured market quote exists for an option at the moment of a fill, Quantradin uses it: buying at the real ask, selling at the real bid, never the friendly midpoint in between. When no measured quote is on record, it falls back to an honest estimated spread around the last traded price, and labels that fill as estimated so you always know which is which. Either way you never get the flattering mid-price fill most backtests quietly assume — the number you see is the number you could have gotten.

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