One price payout, two different units
A contract can be quoted in dollars while paying its price profit or loss in a coin. A second number appears when that coin amount is valued in dollars, Singapore dollars or another reporting unit. The second number depends on a conversion rate and a valuation instant that the first calculation does not establish.
This worksheet keeps those layers visible. It calculates the reciprocal-price payout, deducts only a supplied coin fee amount, and optionally values those results using a separate dated rate. The gross quote equivalent at the reference price is shown as a mathematical comparison. It is not an extra cash flow or a second payment to add to the coin result.
Resolve the amount field before entering a number
For this formula, face value means the whole position amount expressed in the quote denomination. It is neither the number of coins posted as collateral nor necessarily the contract count. Write down the multiplier and its unit from the exact instrument specification before transforming an order-ticket amount.
Deribit documents an instructive inverse-futures example: a BTC future contract represents 10 USD, and an order amount of 1000 USD corresponds to 100 contracts. Settlement is in BTC. That example explains why the number 1000 cannot be treated as 1000 BTC or blindly renamed 1000 contracts. Other products require their own specification; the calculator does not select a venue or infer a multiplier from a symbol.
Sources: Deribit — Inverse Futures: denomination and contract size.
Work through the original example without a floating-point shortcut
For a long, gross coin payout is F times (1/E minus 1/X), where F is quote face value and E and X are quote units per settlement coin. A short uses the negative of that result. In the retained example, F=1000 USD, E=50000 USD/BTC and X=55000 USD/BTC. The exact result is 1/550 BTC, displayed as approximately 0.001818181818 BTC.
Multiplying that exact coin amount by the supplied reference price 55000 USD/BTC gives 100 USD. This is a quote equivalent at that particular price, not the contract settlement unit. Reversing long to short changes the sign. A lower exit price changes the long result to a loss. No leverage field belongs in this price-payout identity.
For a position built from several inverse entries, the supplied average entry must follow the exact provider formula: total quote face divided by the sum of each quote face divided by its entry price. This is the face-weighted harmonic average, not an arithmetic average of prices. This single-entry worksheet does not reconstruct or verify that aggregate.
Sources: Bybit — P&L Calculations, Inverse Perpetual and Expiry Contracts.
An exit, a mark and a last price are not interchangeable records
Choose which kind of price the reference represents. A mark reference describes a valuation using a mark; a supplied actual exit describes a price-payout calculation using that exit. Unknown is available when the record does not establish the role. Changing this label does not alter arithmetic or certify that an execution took place.
Bybit distinguishes unrealized price P&L from closed results that include trading and funding costs. This tool intentionally stops at a narrower scope: reciprocal price payout minus the fees you explicitly enter. A result labelled net here is net of those supplied fees only. It is not a complete account statement, liquidation estimate or leverage return.
Sources: Bybit — P&L Calculations, Inverse Perpetual and Expiry Contracts.
Unknown fees must not disappear into a zero
The original worked example explicitly supplies 0 BTC in fees, so its net equals its gross. Delete that value and the gross calculation remains available while supplied fees and net become unknown. This avoids reporting an apparently complete net amount merely because one input was left empty.
Fees already have to use the settlement coin. Do not type a USD fee into the BTC field or convert it at an unstated rate. This form accepts non-negative charges, not a signed multi-asset ledger. Rebates, funding and other cash movements need their own documented records and are outside this result.
The Singapore-dollar figure requires an independently stated rate
The additional example assumes 70000 SGD per BTC at a user-supplied instant. Multiplying the exact 1/550 BTC gross by this rate yields 1400/11 SGD, approximately 127.272727272727 SGD. This assumed rate is not a live quote, a tax rate or a claim about what a conversion would execute for.
If the reporting currency, rate or rate timestamp is missing, reporting values remain unknown even when the coin payout is known. The form never inserts a rate of one, silently reuses the exit price or assumes that USD and SGD are interchangeable. Using the settlement coin as the reporting unit is permitted only with an explicitly supplied rate of exactly one.
A 16:05 UTC valuation belongs to the next Singapore date
Singapore standard time is UTC+8. The hypothetical rate record at 2026-10-20T16:05:00Z therefore belongs to 2026-10-21 at 00:05:00 in Singapore. The loaded expected date of 21 October matches. Entering 20 October produces an explicit mismatch while retaining the same original timestamp, rate and coin arithmetic.
That difference is useful when a saved rate, journal entry and contract close straddle midnight. It is a check on the supplied record date, not a rule choosing a legally required valuation time. The worksheet does not infer where the reader lives, whether the venue serves that location or which conversion method a reporting obligation requires.
Sources: Singapore BCA — Site Management Data Standards v1.1, page 65.
Keep precision and evidence with the saved result
Reciprocal prices can produce repeating decimals. Calculations therefore use reduced rational numbers, with no intermediate rounded coin amount fed into valuation. Display values use twelve decimal places. When a nonzero amount lies below that display precision, the interface and CSV retain its direction and an exact fraction instead of presenting it as a measured zero.
The download retains the inverse-contract-pnl.csv filename and measure,value,unit layout. Original gross, supplied-fee and net measures remain, followed by exact fractions, precision notes, valuation inputs and the Singapore date check. Negative exported values receive a protective apostrophe for spreadsheet safety. Edits invalidate the result; copy failure leaves a visible manual-copy field. Keep the source records separately because this is a calculation export, not their authentication.
Use the completed check before considering the optional offer
A useful finished record states the contract type, quote face amount, price roles, settlement coin, fee coverage and any separate valuation rate and instant. If any of those are unknown, preserve that limitation rather than searching for a more convenient total.
The tool and explanation are available here without signing up. The optional destination is this publisher's existing Telegram offer for crypto signals, setups and market updates. Visiting it does not verify the input records, improve the arithmetic or complete missing account information.
Worked examples
Example 1
- side
- long
- quote face value
- 1000
- entry price
- 50000
- exit price
- 55000
- fees settlement
- 0
- settlement asset
- BTC
- quote asset
- USD
- reference kind
- exit
- reporting currency
- SGD
- settlement to reporting
- 70000
- valuation timestamp
- 2026-10-20T16:05:00Z
- journal date
- 2026-10-21
- gross exact
- 1/550
- gross
- 0.001818181818
- net
- 0.001818181818
- gross quote equivalent at reference
- 100
- gross reporting
- 127.272727272727
- gross reporting exact
- 1400/11
- journal date matches
- True
Original coin example retained; the separate 70000 SGD/BTC rate is hypothetical and dated.
Example 2
- change
- Leave fees_settlement blank
- gross exact
- 1/550
- net
- unknown
- net reporting
- unknown
Missing fees do not become zero.
Example 3
- change
- Change journal_date to 2026-10-20
- journal date matches
- False
- gross exact
- 1/550
Singapore date membership changes the audit, not the payout.
Questions before you use the result
Can I enter my contract count as face value?
Only after the exact specification establishes the quote face value per contract. This field requires the total quote denomination.
Is the SGD result another payment?
No. It is a separate valuation of the same coin amount at the supplied rate and instant; do not add both results.
Does a net result equal the venue closed P&L?
Not necessarily. It deducts only the supplied non-negative coin fees. Funding and other cash flows are excluded.
Why does an empty timestamp hide the reporting value?
The added valuation is explicitly dated. The coin calculation can remain known while the valuation record is incomplete.
Primary sources and scope
- Bybit — P&L Calculations, Inverse Perpetual and Expiry ContractsChecked 2026-10-20. Reciprocal long/short payout uses settlement coin; price-reference roles and closed-P&L costs differ. Only the formula and scope distinctions are used; source worked-example rounding is not reproduced.
- Deribit — Inverse Futures: denomination and contract sizeChecked 2026-10-20. The documented BTC inverse future has USD contract size and BTC settlement. Order amount is USD face denomination, distinct from the resulting count of contracts. This is a checked documentation example, not a live instrument lookup.
- Singapore BCA — Site Management Data Standards v1.1, page 65Checked 2026-10-20. Page 65 identifies +08:00 as Singapore Standard Time (UTC+8). Used only for timestamp notation and date arithmetic; no construction, trading, legal or tax requirements are inferred.
Prepared from the sources listed above. Examples and calculations explain a method; they do not predict prices or certify an investment. Geographic time references do not establish where a trading service is available. Dated schedules can change: consult the named publisher before relying on a future event.