# Sizing presets: shares, dollars or risk

> Set Scalpel's four buy presets to a share count, a dollar clip or a dollar risk from an ATR, swing low or cents stop, and see the size each press will buy.

Source: https://scalpeltrade.com/guides/sizing-presets
Guide 4.1, Placing trades. Beginner, 8 min read.
Checked with Scalpel 1.12.8 on 2026-10-15. By Scalpel Team.

**In short:**

Scalpel has four buy presets, one per key (`Shift`+`1` to `Shift`+`4`), and each one sizes the order one of five ways: a fixed share count (**Shares**), a dollar amount (**Notional**), or a dollar risk worked out from a stop (**Risk (ATR)**, **Risk (Low)** or **Risk (Cents)**). Pick the kind in the order bar's method dropdown or in **Settings > Sizing**. The line above each buy button shows the dollar size that press would buy at the current ask, so you never fire blind.

How many shares you buy decides how much a bad trade costs you. A fixed share count risks very different money on different stocks; a risk preset keeps the loss at your stop the same on every trade. This guide covers all five kinds, the default ladder, and how to set them up.

Fast small-cap scalping carries a significant risk of loss, and most people who try it lose money. Sizing is your first line of defence: start small, in SIM, and keep the loss per trade to an amount you could take ten times in a row.

**Before you start:**

- Scalpel connected and a symbol loaded on a desk ([guide 1.4](https://scalpeltrade.com/guides/connect-interactive-brokers), [guide 2.1](https://scalpeltrade.com/guides/load-symbols-and-desks)).
- SIM mode while you try the kinds out ([guide 6.1](https://scalpeltrade.com/guides/paper-trading-sim)).

## The five kinds

| Kind | You set | Shares bought | The stop it arms |
|---|---|---|---|
| **Shares** | A share count | Exactly that many | ATR stop (below) |
| **Notional** | A dollar clip | Clip / ask, rounded down | ATR stop |
| **Risk (ATR)** | Dollars of risk | Risk / ATR stop distance, rounded down | 1.5 x ATR under the fill |
| **Risk (Low)** | Dollars of risk | Risk / (ask - recent low), rounded down | The same distance under the fill |
| **Risk (Cents)** | Dollars of risk | Risk / Stop (c), rounded down | Exactly Stop (c) under the fill |

Every kind arms a working stop, a wider catastrophe net and a take-profit when it fills ([guide 5.1](https://scalpeltrade.com/guides/how-stops-work)). The difference is whether the stop decides the size (the three risk kinds) or the size is fixed and the stop simply follows (Shares and Notional).

The share count is worked out the instant you press, from the live ask, and always rounded down to whole shares. So a $100 risk preset never puts more than $100 at risk to the stop, before slippage and fees. If the sum comes to zero shares (for example a $1 risk against a $1.50 stop), the order is refused with **Order size resolves to zero shares**.

## The default ladder

A fresh install has all four presets on **Shares**: 100, 250, 500 and 1,000 shares. Each preset also carries a ready value for the other kinds, so switching the method dropdown gives you a sensible ladder straight away:

| Key | Shares | Notional | Any risk kind |
|---|---|---|---|
| `Shift`+`1` | 100 sh | $2,500 | $25 |
| `Shift`+`2` | 250 sh | $5,000 | $50 |
| `Shift`+`3` | 500 sh | $10,000 | $100 |
| `Shift`+`4` | 1,000 sh | $25,000 | $200 |

The buttons read the way the cheatsheet does: **100 sh**, **$2500**, **Risk $25**.

## Set your presets

### 1. Pick a kind for all four buttons on the order bar

The quickest way is the method dropdown (1) on the order bar under the chart. Choosing a kind switches all four presets to it at once and fills in the ladder value above for any preset that has none. Your choice is saved straight away.

*Screenshot: The method dropdown open (1). The kind it shows is the kind of your first preset. Demo data.*

### 2. Or set each preset on its own in Settings

Open **Settings** (`Ctrl`+`,`), then **Sizing**. Each row is one key: the kind on the left, the value in the middle, and the unit after it: **shares**, **$ / clip** or **$ risk**. Values are whole numbers. Click **Apply** to save, or **Cancel** to throw the changes away.

*Screenshot: Settings, Sizing: the kind list open on the Shift+1 preset, with the five kinds. Demo data.*

### 3. Mix kinds if it suits you

Nothing forces the four keys to match. A common mix is two fixed share counts for quick starter clips and two risk buttons for planned entries. The order bar's dropdown then shows the first preset's kind, and each button keeps its own label.

*Screenshot: Two Shares presets and two Risk (Cents) presets in Settings, Sizing.*

*Screenshot: The same presets on the order bar: 100 sh and 250 sh, then Risk $100 and Risk $200, each with the dollar size it would buy at a 5.71 ask. Demo data.*

**Note.**

The **Stop** stepper for Risk (Cents) only shows on the order bar when the first preset is Risk (Cents). With a mix like the one above, change the cents stop in **Settings > Stops > Risk (Cents) sizing** instead.

### 4. Read the size line before you press

The small line above each buy button is the dollar size that press would put on at the current ask, using exactly the sizing the order will use: **$571** over **100 sh** at 5.71, **$1.9k** over **Risk $100** with a 30c stop. A dash means there is no ask yet, or the preset sizes to zero. Check it whenever you switch to a stock at a very different price.

## Shares and Notional

**Shares** is the simplest: press `Shift`+`3` and you buy 500 shares, whatever the price. Your risk is whatever the stop distance happens to be on that stock.

**Notional** buys a dollar amount: shares = clip / ask, rounded down. $2,500 at a 5.71 ask is 437 shares ($2,495). It keeps the money tied up the same from stock to stock, which helps with buying power, but your risk still changes with the stop.

*Screenshot: Notional: the $2500 to $25000 ladder, each size line a little under its clip because of rounding down. Demo data.*

## Risk (ATR): the stop sized to how much the stock moves

ATR (average true range, see the [glossary](https://scalpeltrade.com/guides/glossary#atr)) is how far a stock typically moves in one bar. Risk (ATR) puts the stop at **1.5 x the 14-bar ATR on the 1-minute chart** and sizes so that stop costs your risk. A jumpy stock gets a wider stop and fewer shares; a quiet one gets a tighter stop and more.

Two limits keep the stop sane:

- **A floor.** The stop is never tighter than **Stop floor (c)**, 20c by default, or 1% of the price if that is smaller (and never under 1c). On a $5.71 stock the floor is about 6c; on a $50 stock it is the full 20c. The floor also stands in when there is not enough candle history for an ATR yet.
- **A ceiling.** The stop is never wider than 40% of the price.

Worked example: ABCD at 5.71 with a 1-minute ATR of 8c. 1.5 x 8c = 12c, above the 6c floor, so the stop is 12c. A **Risk $100** press buys 100 / 0.12 = 833 shares, about $4,756.

The ATR settings live in **Settings > Stops** ([guide 11.3](https://scalpeltrade.com/guides/settings-stops)). They also size the stops for Shares and Notional entries.

*Screenshot: Settings, Stops: the ATR multiples, timeframe and period, and the cent floors that shape the Risk (ATR) stop.*

## Risk (Low): the stop under the recent swing low

Risk (Low) puts the stop just under the lowest low of the **last 20 one-minute candles**, by 0.05% of the price or 1c, whichever is more. The distance from the ask to that level sizes the trade.

Worked example: the 20-bar low is 5.45, so the stop level is 5.44. With the ask at 5.71 the distance is 27c, and **Risk $100** buys 100 / 0.27 = 370 shares.

The stop is then armed that same distance under your actual fill. If you fill at the ask it sits right at 5.44; if the order walks up the book, it sits a little higher. If there is no usable low (no candles yet, or the low is not under the ask), Risk (Low) falls back to the ATR stop.

**Tip.**

Risk (Low) suits a pullback entry, where the low of the pullback is the level that proves you wrong. After a long run with no pullback, the 20-bar low can be far away: watch the size line shrink and decide whether that wide stop is really the trade.

## Risk (Cents): a fixed stop in cents

Risk (Cents) puts the stop a fixed number of cents under the fill, 30c by default, and sizes to it: $100 at 30c is 333 shares. It is the most predictable kind and has its own guide: [guide 4.2](https://scalpeltrade.com/guides/trade-fixed-dollar-risk).

## What can go wrong

- **The order is refused by a cap.** Your fat-finger and max-position caps block the whole order rather than shrink it, and tight stops ask for big share counts. In SIM, a buy bigger than your free SIM cash is refused too. See [guide 7.2](https://scalpeltrade.com/guides/fat-finger-and-position-caps).
- **The size line jumps when you change symbol.** That is the point of risk sizing: the same $100 buys 833 shares of a quiet $5 stock and 125 shares of a jumpy $12 one. Read the line before you press.
- **Values for the other kinds reset.** Settings saves only the value for the kind each preset is on. If you later switch kinds on the order bar, an empty value is filled from the default ladder, so check the buttons after a switch.

For why sizing from the stop matters, read the blog post [Sizing by risk](https://scalpeltrade.com/blog/sizing-by-risk).

## Questions

**What is the best sizing method for day trading?**

Sizing by risk: decide the dollars you will lose if the stop is hit and let the stop distance set the shares. In Scalpel that is Risk (Cents), Risk (ATR) or Risk (Low). Fixed share counts quietly change your risk from stock to stock.

**Why did Scalpel buy fewer shares than I expected?**

Every kind rounds down to whole shares, and risk kinds size from the live ask at the moment you press. A wider stop than you assumed (an ATR floor, a far swing low) also means fewer shares.

**Can each buy key use a different sizing method?**

Yes. Set each row's kind in Settings > Sizing. The order bar dropdown shows the first preset's kind; choosing from it switches all four.

**Can I use cents in a preset value?**

No. Preset values are whole numbers: shares, whole dollars of clip or whole dollars of risk.

**Does the preset change the stop on a Shares entry?**

No. A Shares or Notional entry arms the ATR stop, the same as Risk (ATR). Only the risk kinds use their stop to size the order.