Preuval
Preuval

Independent verification · perpetual futures

We don’t trust the screenshot.
We recompute it.

Preuval pulls your raw exchange records — every fill, funding payment, and transfer — rebuilds your equity curve with exact decimal math, reconciles it against the exchange’s own balance snapshots, and seals the result with SHA-256. If any input changes, the seal changes.

Read-only API keys. We can’t trade or withdraw, and keys are never written to disk.

  • raw exchange data — not self-reported
  • exact decimal math — zero float drift
  • deterministic SHA-256 seal
  • re-verifiable without the raw data

How verification works

Four deterministic steps. The same inputs always produce the same result — that’s what makes it checkable.

  1. Pull the raw data

    Connect a read-only BloFin API key. We page through the primary records themselves — trade fills, funding payments, deposits and withdrawals, balance snapshots — and store every raw response byte-for-byte. Each file is hashed into a manifest before anything is computed.

    output
    GET /api/v1/trade/fills
    GET /api/v1/account/bills
    GET /api/v1/asset/deposit-history
    GET /api/v1/account/balance
    → raw pages stored · sha256 per file

  2. Recompute from first principles

    The engine replays the account event by event: positions, average entry, realized and unrealized PnL, fees, funding, transfers. All arithmetic is exact decimal — the math an auditor would do by hand, never binary floating point.

    output
    realized = (52,105.00 − 51,240.50) × 0.42
    = +363.090
    equity = Σ realized − fees + funding + transfers

  3. Reconcile against the exchange

    The recomputed curve is compared with the exchange’s own balance snapshots at each point in time. Agreement within $0.01 means the record is internally consistent — the fills you show actually produce the balance you claim.

    output
    t computed exchange Δ
    03-14 00:00 12,408.13 12,408.13 0.00 ✓
    04-02 00:00 13,911.07 13,911.07 0.00 ✓

  4. Seal it

    Exchange, session, file manifest, time window, mode, and engine version are serialized canonically and hashed. The seal is deterministic: rerun the verification and you get the same hash. Alter a single fill and you get a different one. The exported bundle can be re-verified by anyone — without your raw data.

    output
    seal e3a1c9f2…4b7d
    1 fill edited →
    seal 91d407be…a2c3 ≠ TAMPERED

Display is not verification

Track-record tools fall into two camps: dashboards that display what a trader or broker reports, and on-chain explorers that can’t see inside a centralized exchange. Neither recomputes anything.

capability matrix
Capability comparison between Preuval, Kinfo, TraderSync and Nansen
PreuvalKinfoTraderSyncNansen
Data sourceRaw exchange API recordsBroker-linked syncManual imports & syncOn-chain wallets
Covers CEX perpsYes — BloFin, more comingPartiallyAs a journalNo
Independent recomputationFull equity replayNoNon/a
Tamper-evident sealDeterministic SHA-256NoNoNo
Third-party re-verificationExportable bundleNoNoPublic chain data

Kinfo, TraderSync and Nansen are useful tools — for social broker-linked sharing, journaling, and on-chain research respectively. None of them claim to independently verify centralized-exchange perp records. Comparison reflects publicly documented capabilities, July 2026.

The output is a link, not a PDF

Every verification produces a public report page anyone can open: the verdict, the recomputed equity curve, reconciliation results, audit and credibility scores — and the seal. Send the link instead of a screenshot. If the data behind it ever changed, the seal wouldn’t match.

Independently verified by Preuvalsample data
VERIFIEDblofin · cash mode · 90 days
Return
+24.6%
Max drawdown
−8.2%
Snapshots
31/31
SHA-256 verification seal

Built for the people who get lied to

Traders

Raising capital or selling signals? Replace “trust me” with a sealed link. Your counterparty can check the math instead of taking your word.

screenshot → sealed link

Prop firms

Screen external track records at intake. A candidate’s claimed PnL either reconciles against their exchange’s snapshots or it doesn’t — before you fund them.

claims → reconciled records

Copy-trade platforms

Gate leaderboard listings on verification. Every listed strategy carries a seal your users can independently re-check.

leaderboard → verified leaderboard

Your track record, recomputed and sealed

One read-only key. A few minutes. A verification that outlives the argument.

Read-only API keys only. We never place trades or move funds.