A common question that always comes up on this site is “How Do I Calculate Lot Sizes on MT5?” Well today we are going to take a dive into lot size calculators for MT5 and how to correctly calculate your lot sizes on the relatively new but extremely popular MT5 platform.
TLDR: Use the Volume setting to adjust your lot size on MT5 – it’s called ‘Volume’. Remember to set a stop loss and use risk responsibly and proportionate to your account size.
What is MT5?
MT5, or MetaTrader 5, is one of the most widely-used trading platforms in the world. Developed by MetaQuotes, it offers access to forex, commodities, indices, stocks, and cryptocurrencies, depending on your broker.
MT5 is the more modern, upgraded version of the older MT4 platform. It’s faster, more powerful, and allows trading across multiple asset classes — not just forex.
When you open a position on MT5, you have to set the Volume field — this is where your lot size comes in. The platform assumes you understand lot sizing when you enter a trade — but the reality is, many traders don’t.
How Does MT5 Differ from MT4?
Before we dive into lot sizes, it’s important to know a few key differences between the MT4 and MT5 platforms:
| Feature | MT4 | MT5 |
|---|---|---|
| Assets | Mostly Forex | Forex, stocks, indices, commodities, crypto |
| Execution Speed | Slower | Faster |
| Indicators | Limited | Expanded (38 built-in, 44 graphical objects) |
| Pending Orders | 4 types | 6 types |
| Timeframes | 9 | 21 |
| Hedging & Netting | Hedging only | Hedging and Netting |
In short:
MT5 is a multi-asset, more flexible platform than MT4, designed for faster execution and more complex trading strategies.
But lot sizing principles are broadly the same — and just as important on both platforms.
A video I found really helpful in explaining this difference is this one from Nick from TransparentFX:
He quickly and simply breaks down the difference between the two platforms better than I ever could – so check it out for more info if you still need a bit of info on the differences.
What Even is a Lot Size?
Before we get practical, let’s quickly make sure we’re all on the same page.
In MT5, when you place a trade, you have to choose the Volume. This volume represents your lot size — essentially how big your trade is.
In forex, the industry standard lot sizes are:
- 1.00 lot = 100,000 units (Standard Lot)
- 0.10 lot = 10,000 units (Mini Lot)
- 0.01 lot = 1,000 units (Micro Lot)
In simple English:
If you’re trading GBP/USD and you buy 1.00 lot, you’re effectively buying £100,000 worth of GBP against the dollar.
Important:
“If you trade a smaller lot size, your risk per pip movement is lower. If you trade a larger lot size, your risk per pip movement is higher.“
Lot Size Calculator
Rule of thumb:
- 1.00 lot = roughly £7–£8 per pip on GBP/USD
- 0.10 lot = roughly £0.70–£0.80 per pip
- 0.01 lot = roughly £0.07–£0.08 per pip
It varies slightly depending on the currency pair, but this gives you a rough guide.
Why Getting the Lot Size Right is So Important
Honestly, sizing your trades wrong is one of the fastest ways to blow your account. I’ve seen good traders wipe out weeks of profits because they accidentally risked 10x more than they meant to — all because they didn’t properly calculate their lot size.
When you trade without calculating, you’re gambling. That’s part of the reason we created the leading lot size calculator in the UK. We understand how important this is to trading every day.
When you trade with a calculated lot size, you’re managing your risk like a professional.
The Practical Way I Calculate Lot Size on MT5
Alright, now for the part you’re here for.
Here’s exactly how I work out my lot sizes when I’m using MT5. After downloading the app, here are my 4 super simple steps:
Step 1: Decide on Your Risk
The first thing you need to know is how much you are comfortable losing if the trade goes against you.
Personally, I usually risk 1% of my account per trade. Sometimes less if I’m being extra cautious.
Example:
- Account balance = £5,000
- 1% of £5,000 = £50
- I can risk £50 maximum on this trade.
Top Tip:
If you’re a beginner, stick to risking 0.5–1% of your balance. Stay in the game longer while you learn.
Step 2: Set a Stop Loss
This is the second key part. Every trade must have a stop loss.
Your stop loss is the point at which you’ll close the trade if it moves against you.
For example:
- You buy GBP/USD at 1.2500.
- You put your stop loss at 1.2450.
- That’s a 50-pip stop loss.
You need to know how many pips your stop loss covers because it directly affects your lot size calculation.
Pro tip:
Don’t randomly pick a number of pips. Set your stop loss based on structure — like recent highs/lows, support/resistance.
Step 3: Use a Lot Size Calculator
Now that you know:
- How much you want to risk (£50)
- Your stop loss (50 pips)
Use a Lot Size Calculator to work out exactly how big your lot should be.
There’s no need to mess around doing manual calculations.
There are brilliant free calculators online that do it for you in seconds. Here’s how:
- \Go to a free online calculator (like Lot Size Calculator or MyFXBook).
- Input:
- Account currency: GBP
- Account balance: £5,000
- Risk percentage: 1%
- Stop loss: 50 pips
- Currency pair: GBP/USD
- Hit “Calculate”.
It will tell you:
- Lot Size: Around 0.13 lots.
So in MT5, you would type 0.13 in the Volume box when opening your trade.
That’s it. You’re done.
Step 4: Place Your Trade Correctly on MT5
Now that you know your lot size:
- Open the New Order window in MT5.
- Under Volume, type in 0.13.
- Set your stop loss and take profit levels.
- Execute the trade.
Important:
Always double-check that the lot size is correct before hitting buy or sell.
My Advice for Beginners on MT5
I’ve coached a lot of traders through this, and here are some practical points to look out for – based on real-world experience:
1. Always Calculate Before You Trade
Never eyeball it. Never guess. Always plug the numbers into a calculator before placing a trade.
2. Use Micro or Mini Lots (or even a Demo) if You’re Starting Small
If you’re trading a small account (say £500–£2,000), don’t be afraid to use micro lots (0.01) or mini lots (0.10).
The goal is to stay in the game — not swing for the fences and hit that million-pound account in 2 months – trust me, it’s not possible.
3. Don’t Use Huge Lot Sizes Just Because You Can
Even if your broker lets you trade 1.00 lot, don’t unless you actually have the account size to handle it safely.
A good rule of thumb from a previous article of ours:
- £500 account = mostly micro lots (0.01–0.05)
- £2,000 account = micro or mini lots (0.01–0.20)
- £10,000 account = mini to small standard lots (0.10–0.50)
4. Remember Different Assets Move Differently
A 50-pip move on GBP/JPY feels very different from a 50-point move on the S&P 500 index.
Lot size calculators like ours usually ask you to specify what you’re trading (forex, commodities, indices) for this reason.
Always check you are using the right asset settings.
5. Bookmark Your Lot Size Calculator
Honestly, treat it like your trading bible.
Save the link on your phone, laptop, whatever you use to trade.
Calculate every trade — no exceptions.
What Happens If You Don’t Calculate Lot Size Correctly?
I’ll be brutally honest — miscalculating lot sizes is how most beginners lose money.
Here’s what tends to happen:
- You accidentally risk 10–20% of your account on one trade.
- One bad move wipes out months of progress.
- You start chasing losses.
- You blow your account.
It’s not about being clever. It’s about protecting yourself so you have enough capital to take the good trades when they come.
Learning to calculate your lot size properly is one of the first signs that you are becoming a professional, disciplined trader.
Final Thoughts
If there’s one habit that’s changed my trading more than anything else, it’s this:
I calculate my lot size before every single trade — no matter how small.
MT5 is an amazing platform, but it doesn’t protect you from yourself.
It’s up to you to be disciplined, structured, and professional in how you place trades.
If you’re serious about succeeding, start every trade with the same simple steps:
- How much am I willing to lose?
- Where is my stop loss?
- What’s the correct lot size for this trade?
And then use a calculator to check it.
It’s simple, it’s boring, but it’s effective.
Trust me — once you start doing it properly, you’ll wonder how you ever traded without it.
