Please refer to this page to get started using the extension:
Trading is simply “the buying, selling or exchanging of assets.”. In financial markets, “trading” or “day trading” is mostly referred to in the context of short term sellers or buyers looking for a profit - buying low and selling high (or selling high and buying in lower when shorting assets).
It is, however, important to remember that a lot of trading in all markets is done without short term profits in mind (companies may need foreign currency to buy goods in other markets, etc.).
Well, the similarities are many, but in my opinion, there are a few major differences: Gambling is (mainly) random. You bet on a result or outcome and hope for the best!
In trading, you have information and analysis that points towards this setup being profitable. Not necessarily this particular trade, but it should statistically be more likely to play out as expected than not. The main point is that if you do not have a proven system, you do not have an “edge” in the market, and you are gambling with your money!
A proven system means that your particular trading system has proven statistically profitable in the long run.
This manual will not go into further details about this subject, but there is on critical takeaway here: All long term profitable trading systems will need strict money management as a foundation! One major issue is that you need to be able to quantify your potential loss (if the trade does not play out as you hoped) vs. how much you will potentially gain from your profit. Furthermore, you need to limit your loss to prevent a strike of bad trades does not wipe out your trading account. This is crucial if you want to be consistently profitable in the long run!
Most trading systems are based on the principle that you risk a set percentage of your trading account on every trade. This could be 1%, 2%, or something else. You may see some traders refer to this as R.
A trader may explain how he “risked 2R on this particular trade”. Just keep in mind that the number of potential drawdowns in your trading system should play a major role when it comes to deciding how much to risk on every trade.
This manual will not dig deeper into this subject. If you want to know more about this, I will encourage you to read up on “Monte Carlo analysis”. The Trader Rookie Forex Position Size calculator Extension calculates all position sizes based on a set percentage of your trading account size.
The calculator features 3 diffent color themes.
Click the button to toogle between the 3 different themes:
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Reset all inputfields to get ready for a fresh calculation.
The calculator user-interface is easy to move around inside the browser-tab. Simply press and hold the icon while you reposition the UI.
This will hide the calculator user-interface. Click the extension icon in the upper right corner of the browser tab to re-open the calculator at any time.
If you prefer it is also possible to toggle the UI on/off with
The price dial is optimized to use with touch screens but could also be used with a mouse or touchpad.
Activate one of the Price Dial Buttons to select the desired input field, then press and hold the dial and rotate clockwise or counterclockwise to adjust the price. Price adjustment is accelerated when you continue turning the dial. To fine-tune the pricepoint after large adjustments: release the dial then press, hold and rotate the dial again.
To make small adjustments press and hold the dial and move your finger outside the dial in a straight line from the center of the dial. This will make it far easier to make micro-adjustments.
Price dial buttons are used in conjunction with the
price dial. Toggle on the desired input field and spin the dial: It is that easy!
This is the position size calculated in LOTS or UNITS according to your preferences.
Please be aware that the calculator does not take any fees or commissions into account when calculating position sizes.
The Clipboard icons makes it straightforward to copy pricedata from the calculator to your brokers trading-interface.
Settings to activate this feature. Afterwards you can copy the price to your clipboard without loosing focus on the inputfield in your brokers interface. Please note that your decimal seperator settings are carried over when copying a price value.
Open the settings page in a separate tab here.
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If you need further help using the extension, you can always revisit the online manual from here.
If you are using a mouse to navigate, you can make quick changes to the price using the scroll wheel. Activate this feature in the
Click the inputfield and scroll until you get to the desired pricepoint. This is useful in a fast paced marked!
This feature is not recommended for use with touchpads or trackpads, as it may lead to unintentional accidental price adjustments in input fields.
Set leverage manually when you calculate position sizes or go to settings and set leverage for all pairs at once or for individual pairs
Although the leverage input is an optional input field, and calculations will work just fine without it, a leverage value is required to calculate
initial market impact
Set stoploss size as you prefer: Enter a specific price point or set the size of the stop loss in pips.
You can toggle between position sizes calculated in units or LOTS.
If you want to, you can toggle between LOTS sizes calculated in standard- mini- or micro LOTS on the settings page here
Bull or bear?
Make your choice and
toggle trade direction here.
Click the tradepair button and select tradepair.
Missing anything? You have almost endless possibilities to construct your own tradepairs in the Settings window.
Hover over any tradepair in the calculator to see the description. This is especially helpful if you are new to trading forex and still not familiar with all currency abbreviations.
This slider will change the content of the dropdown when clicking the
trade pair button
The calculator makes it easy to get a visual presentation of the current position size calculation.
This is similar to risk/reward ratio stats that you are probably familiar with from various charting packages.
This is a fast way of visually ensuring that you didn't make a type error!
Similar to the calculator itself, you can reposition the visual presentation - using the icon in the upper right corner.
If the calculations contain any error(s), the graph will be hidden until the error(s) is corrected.
Please refer to the section about errors for further details.
The calculator shows you the initial margin impact of the trade setup.
On the right side of the margin output, a gauge will indicate how much of your full margin account that is required for the calculated trade.
If the output field turns red, the initial margin requirement for this setup is larger than your margin account and will not be possible to fulfill.
A leverage value is required to calculate the initial margin impact. Please refer to your broker for margin data on trade pairs.
If you are new to margin trading it is highly recommended to take some time learning concepts like "maintenance margin" and "forced liquidations". Otherwise, you could end up with some unpleasant surprises.
Set the risk amount as a percent of your full account size.
Under normal market conditions, this will limit your loss to this set percentage, if your stop loss gets triggered.
However, in some circumstances, slippage and gaps may occur leading to larger losses.
It is therefore crucial that you never see stop losses as guaranteed when trading.
The table on the left side of the calculator window will provide you with various info on the calculated trade setup.
On top, you will get the Profit & Loss, shortened PnL calculated to your stop-loss order, and the various take profit targets.
Furthermore, you get the effect on your account balance (BAL) calculated in percentage. Please note that the percent loss may differ slightly from the entered Risk amount. This is due to the calculator striving for calculations as close to the desired risk amount as possible: In some instances, especially with small trade accounts and low leverage - the difference may, however, be tangible.
The bottom part of the table will show you risk-reward-ratios (RRR) and take-profit sizes at the various take profit levels.
The calculator will actively monitor, that the input fields do not contain obvious errors.
An example could be if the stop loss price is placed above entry in a long trade.
This would result in this error:
Correct the stop loss price, by entering a price lower than entry.
Alternatively, you could switch the trade direction to short to remove the error.
Navigating the calculator with a mouse or touch-/numpad is straightforward and intuitive. A couple of details are, however worth mentioning:
Hover the different sections of the calculator to get tooltips to guide the use of the calculator. This is especially helpful when new to trading forex: Hower over any of the trade pairs in the dropdown to get the full name of the pair. When selecting an input field, you can single-click the field to place the courser at any place in the field. This way you can delete a single digit and replace it with another-. Alternatively, double-click the input field to select all input. This way you can easily just enter a different price.
The calculator can also be used on touch-screens. The
price dial combined with the price dial buttons makes it easy to adjust price input in a hurry.
The calculator is fully navigatable using the keyboard only, for maximized efficiency.
This makes it the best way to calculate position sizes in a fast-moving market.
Furthermore, the settings page is fully navigatable using the keyboard. The only exception is the drag and drop interface where you need to use a mouse or touch.
Toggle the calculator on/off:
Navigate the calculator by tabbing through the input fields and buttons of the calculator interface.
Confirm changes in input-fields by tabbing to the previous or next field.
Press the buttons or confirm selections in dropdown menus:
When tab-shifting to an input field all input will be selected by default.
You can then overwrite all price data in the input field. Simply enter a new price with the numeric keys. Alternatively, use the arrow keys right and left:
...to go to a specific point to delete and reinsert a single digit.
Adjust price data up or down within the input fields:
Alternatively, adjust the price in larger increments:
To construct a new forex pair you simply select the base- and quote currency of choice: And then drag it to the right column."
Select the pair you want to delete in the right column, and drag it to the left column.
The calculator comes preloaded with a variety of different index- and commodity pairs.
To add any of the pairs in the left column to the calculator: Select the desired trade-pair and drag it to the right column.
If you want to, you can construct your own custom pairs in the
Setup Index and Commodity pairs dialog
Simply select the tradepair and drag it to the left column.
Custom pairs will be deleted entirely.
Predefined pairs will be moved to the left column for future use.
You can drag pairs up and down the right column to change the order of the pairs in the calculator
The calculator will operate just fine without entering leverage during calculations. But if you want to calculate the initial market impact for the trade, it is required to set trade pair leverage also.
To save the hassle of setting leverage on every position size calculation, the "set Leverage on Forex pairs dialog" makes it possible to attach leverage to all forex trade pairs individually or collectively.
Select or deselect individual pairs by clicking them directly. You can also toggle all pairs on/off using the "Select All" and "Deselect All" buttons. Set leverage in the input field using the number keys on the keyboard, the arrow up- and down keys - or with the mouse clicking the small spinner-arrows in the input field. Click the "Set leverage" button to attach entered leverage to selected pairs. The "Remove leverage" button can be used to remove any leverage on selected trade pairs.
You can select or deselect individual trade pairs by clicking them directly.
Select all trade pairs - this makes it easy to adjust leverage on all pairs collectively.
Deselect all trade pairs at the same time.
This button will create a new custom trade pair.
After creation, you need to set all mandatory fields marked in red to finish off the construction of the new pair.
Furthermore, it is advisable to add a description and leverage to the pair.
All data on Index- or Commodity pairs is editable.
Enter- or select the desired changes in the input field and confirm with the "SET" button directly underneath each field.
It is possible to attach leverage on all index- or commodity pairs individually or in bulk.
This way you do not have to enter leverage on trade pairs on each calculation.
If a trade pair has leverage attached to it, it will be indicated with a small icon next to the trade pair, revealing the attached leverage amount.
Please refer to your broker's documentation for info on leverage on individual trade pairs.
When selecting a trade pair in the calculator, an icon located in the selection button will make the pair easily recognizable.
To change the icon, select an icon in the icon selection window using the mouse or the keyboard arrow keys. Once the desired icon is selected, press "SET" to change the icon.
The currently selected icon is shown in the upper right corner, above the icon selection window.
Here you can toggle between using point or comma as a decimal separator in the calculator.
The calculator doesn't use point or comma as thousand separators.
When calculating position sizes in lots, it can be done in 3 different ways:
Standard lots (rounded to the nearest whole number). Mini lots (rounded to one decimal place). Micro lots (rounded to two decimal places).
The calculator can be used in a compact layout.
The compact layout will sacrifice the price-dial plus take-profit 2 and take-profit 3 targets, but save you valuable screen space in return.
Enable the use of clipboard icons.
Clipboard icons make it fast to copy price data to your broker's trading interface.
Read more about how to use them
If you have a mouse with a scroll wheel, you can enable fast price adjustment of price values in input fields.
Just select the desired input field and scroll away
This button makes it possible to reset the extension to defaults. Any changes you have made to trade pairs or settings will also be removed permanently.
All browser tabs and -windows with an active calculator will be reloaded as a part of this reset. Please make sure you do not have any unsaved data in (a) browser tab(s) using the calculator.
It is possible to open the calculator in a separate window to make it act more like a stand-alone application.
This is useful when using desktop trading platforms like MetaTrader and cTrader.
Right-click in any browser window and select "Open Forex Calculator in a separate window". "
Due to restrictions on browser extension privileges, it isn't possible to pin the calculator window on top of your trading platform natively. But you can install 3rd party software to add this functionality.
For Windows users, I recommend
WindowTop. WindowTop is a lightweight free software package that makes it possible to pin the calculator-window on top of eg. Metatrader.
This makes it fast and easy to copy price-data from the calculator to your trading interface.
Security should be a major concern for all traders. After all: It's your own hard-earned money: Keeping them safe better be a major priority!
Browser Extensions need access to special privileges within the internet browser to operate as intended. However, the Trader Rookie Forex Position Size extension only rely on privileges that are crucial to its functionality.
Online safety and security have been a major concern while developing the calculator extension.
The calculator is intended for use on top of TradingView or similar charting sites and your broker's online trading interface. Therefore, great lengths have been taken to make sure your private data like passwords and user data on these platforms do not become vulnerable to malicious and unwanted intrusion.
The calculator was developed by incorporating best practices in browser extension development as recommended by Google and Mozilla. These practices include extra layers of protection to prevent malicious and unwanted intrusion and attacks.
The calculator has no "calculate button" per se. But when you make input changes or updates are made to settings, all calculations are updated instantly.
You will get a visual indication that calculations are updated in the left- hand output-area visualized by a checkmark.
No, the calculator has no offline mode. All calculations rely on live exchange rates data.
If your internet connection is down for some reason, the calculator will indicate this with a large offline badge.
You do not have to save anything.
All changes made on the settings page are synchronized instantly to any open calculators and stored for future use. If you are signed into the browser all settings and input from the calculator will be synchronized automatically to all devices. Otherwise, the settings are stored locally on your computer.
Well, first off: You only need to pay attention to contract sizes if you calculate your position sizes in lots. All unit calculations are unaffected by the contract size.
But if you trade with lot sizes, you need to get contract size data from your broker on the pairs you want to trade. Otherwise, you may unintentionally calculate position sizes with (potentially large) errors. Index and Commodity pair contract sizes aren't standardized across brokers in the same way as with forex pairs.
You need to know how many units one contract consists of. This will typically be referred to, as something along the lines of "Contract size" or "Value of one contract".
A quick example:
Your broker offers "XAUUSD" or simply "Gold Cash" in contract sizes of "100 troy ounces". Here the quote-currency for the trade-pair is USD.
Go to the "Setup Index and Commodity pairs dialog" and make sure "lot size" is set to "100" and "Currency" is set to "USD".
In this dialog, it is also recommended to set leverage on the trade-pair according to your broker's specifications.
Please refer to
Setup Index and Commodity pairs dialog for further explanation on editing these values.
All contract sizes can be found for all trade pairs directly in Meta Trader.
In the View menu select "Market Watch" or press Ctrl + M. In the market watch section right-click the tradepair you need to find the contract size for. In the right-click menu select "Specification". In the contract specification dialog you will now be able to see the contract size for this trade pair. To get leverage on the trade pair divide 100 by margin percentage. A margin percentage of 3.33% is equivialent to 30x margin and a margin percentage of 5% is equivialent to 20x margin.
April 22nd, 2021
- New forex data provider - The old data API endpoint suddenly stopped working.
November 2nd, 2020
- Fixed a crucial font-error as a work-around for a bug in Chromium browsers.
October 22nd, 2020
The extension visuals got a full makeover - I hope you like the new design! Fixed a compatibility-issue with saxotraderGo (only relevant if SaxoBank is your broker) - you can now copy the price-data from the calculator seamlessly to Saxotrader. Various "code optimization" behind the scenes - code is running smoother and faster using fewer resources. Clipboard icons are now visible by default. They can still be turned off on the settings page.
September 23rd, 2020
You can now just press enter to confirm input in input fields (you previously had to tab forward to the next field). Default layout is now "compact" when installing the extension. You can still select the standard layout under settings. All unused fields are now disabled when setting initial values - this is done to make the initial setup more intuitive and guided for new users. Fixed an error, where the pop-up about contract size variances on index and commodity trade pairs, occurred more than once in some instances
September 6th, 2020
A new compact layout is now available! Toggle between "standard" and "compact" layout on the settings page. It is now possible to toggle between 3 different color themes! Switch theme on the color-brush in the upper right corner of the user-interface. Fixed an error that prevented recalculations of position sizes when adjusting prices with the price-dial in some instances. Fixed an error that allowed letter input in the risk input field.
August 18th, 2020
Fixed a rare issue where stop-loss PnL and BAL values in the left side table sometimes didn't calculate correctly and showed "NaN". Added some extra error messages on top of the left side table. These will better guide users to know what values are missing. Entry, stop-loss, etc. Fixed an issue where the lower stop-loss output value wasn't removed if the calculator was reset from a different browser tab.
August 7th, 2020