Direct answer
Information about Free Margin can be verified by rebuilding it from stable, account-level components using the same definitions your provider uses. Do not accept one displayed value without checking the inputs (equity, used/required margin, and any adjustments such as outstanding fees or credit/debit rules). If you cannot reproduce the displayed figure from those inputs, treat the difference as a limitation of the provider’s calculation method.
What Free Margin means (definition first)
Free Margin is typically described as the portion of account equity that is not currently committed to supporting open positions. A common mechanics pattern is:
- Free Margin ≈ Equity − Used Margin
Where:
- Equity is the account value including the current value of open positions (unrealized profit/loss) plus cash and any other account components included in equity.
- Used Margin is the portion of margin reserved to keep open trades running under the provider’s margin rules.
Because providers can define “equity” and “used margin” with different inclusions (for example, how they handle commissions, financing, or rounding), verification should focus on matching the provider’s own definitions.
How to verify it with reproducible steps
Step 1: Write down the exact definitions you are verifying
From the provider’s documentation or account statements, note how they define:
- Equity (what components it includes)
- Used/required margin (what positions and instruments it covers)
- Any “adjustments” or special items included in Free Margin (for example, whether certain fees are already reflected)
Assumption to state: you are using the provider’s own calculation basis, not a generic formula.
Step 2: Collect the displayed inputs at the same time
Use one snapshot (or as close as possible) to record:
- Equity
- Used Margin
- The displayed Free Margin
Assumption to state: the numbers refer to the same timestamp and the same pricing basis for open positions.
Step 3: Recalculate Free Margin using the provider’s stated formula
Apply the provider’s documented relationship. If the provider states the same pattern as above, compute:
- Equity − Used Margin = expected Free Margin
Then compare expected versus displayed. Allow for differences from rounding.
Rounding check: if your expected value differs only by a small rounding amount, the method may be consistent.
Step 4: Repeat under a controlled change
To confirm you are not using the right inputs by coincidence, verify again after a controlled change that should affect margin math, such as:
- Opening or closing a position (used margin should change)
- A change in unrealized profit/loss (equity should change)
Assumption to state: you are not changing multiple variables at once, so the direction of the change makes sense.
Step 5: Validate calculation consistency across pages/menus
Some platforms show different “views” (for example, account overview versus risk/margin screens). Verify whether each screen uses the same equity and used margin components, or whether one includes additional items.
Assumption to state: if the components differ, Free Margin can differ even if the provider is behaving consistently.
Evidence, examples, and material limitations
Example of a consistency check
Suppose at time T you record:
- Equity = 1,000 (account currency)
- Used Margin = 250
- Displayed Free Margin = 750
Then the displayed value is consistent with Free Margin ≈ Equity − Used Margin. If the displayed Free Margin is 745 or 760, examine rounding rules and whether the provider includes additional adjustments in Free Margin.
Material limitations and failure modes
- Different definitions of equity: Equity may include or exclude items such as commissions, financing/overnight charges, or other account credits/debits. If your rebuilt calculation omits one included component, you will not match the displayed Free Margin.
- Valuation method differences: Unrealized profit/loss can be computed using bid/ask or mid pricing, or instrument-specific valuation conventions. If your verification uses a different pricing basis than the platform, results won’t reconcile.
- Update timing and delayed refresh: Free Margin may update on different intervals than equity or used margin. A mismatch can occur even when the formula is correct.
- Rounding and currency conversion: If the platform converts margin to a different currency, exchange rates and rounding can create persistent small differences.
These limitations mean that “verification” is not only about the algebra; it is also about matching the provider’s valuation timing and component definitions.