04 — TRACKING - explorer, mempool, pools, flows

What a transaction publishes

A Zcash transaction publishes its version, the pools it touches, its per-pool value balance, its nullifiers, its anchors, its commitments, and its transparent inputs and outputs. All of that is exact. The fee is not among them: a fee is the difference between the outputs a transaction spends and what it pays out, and the outputs it spends belong to earlier transactions, so it is computed here rather than read - and where an earlier output cannot be resolved, this page says so instead of naming a figure. What no transaction publishes is a sender inside the pool, and no amount of arithmetic on the rest produces one - so what follows the public fields is a candidate set, its filters, and the assumptions each filter rests on.
what a query can return
t-address
exact balance, history, counterparties, boundary events
z or unified address
undefined not on chain - exact with your viewing key
txid
public fields candidate sets, N_eff, links
labels
consensus > owner filing > exchange > analyst > behaviour
transaction - v5 - block 3,191,051 - 2026-01-02 18:53:18 - leak class Z_TO_T - severity HIGH
7ae85864... an unshield of 50,000.5541 ZEC to t1dP1MJwfYr9z7EwWxSpefP6s2p7ewaKx9e
valueBalanceOrchard
+50,000.5541
leaving the pool - exact
transparent out
1
single-use address, spent 1h42m later
fee to logical actions
L = 2
10,000 zat - ZIP 317 conventional - at most 2 real spends
anchor depth
1
synced immediately before spending
what this transaction publishes
nullifiers
2 - orchard, one of them likely a dummy
commitments
2 - orchard: change and dummy
anchor
root at 3,191,050 - depth 1
expiryDelta
40 blocks - Zashi family
proof size
2,720 + 2,272 x 2 = 7,264 B - canonical
recipient
t1dP1MJw... - fresh - exact
sender
not on chain, by construction
A

The origin of the spent note

every filter, its cost, and what it assumes
inference chain
  1. 4.92Mraw candidate set, anchor boundno candidates removed
  2. 3.11Mspent-count subtraction-1.81M
  3. 41,208time window, W = 576 blocks-3.06M
  4. 1amount echo, epsilon = 1e-4-41,207
  5. 1N_eff - H = 0.00 bitsrequires disclosure

Link grade MEDIUM - the claim level above says how large the surviving set is; the grade says how much the filter that produced it is worth.

p = 1.00 t1XKfbZY... shielding its entire balance, 52 minutes earlier
  • A single-note spend. The fee of 10,000 zatoshi is ZIP 317 conventional at two logical actions, which bounds the shielded arity at two - one real spend and one likely dummy.
  • Receipt within about twelve hours of the anchor, which is the 576-block window the time filter applies.
  • That the 50,000.96 ZEC shield 52 minutes earlier (tx a7934713...) is the origin. The residual is 0.4059 ZEC, a relative error of 8.1e-6 - about 12 times inside the 1e-4 relative tolerance, and about 254 times outside the v0.2 absolute one of 0.0016 ZEC, which would have missed this link entirely.
  • One external signal would confirm or refute this. The chain alone cannot, and the link is graded MEDIUM rather than HIGH for exactly that reason.
B

The round trip

verified on chain - the endpoints are public and the middle is not
2026-01-02 18:01:43 - 3,191,017t1XKfbZY... shields its entire balance-50,000.96
18:01 to 18:53inside the Orchard pool - 52 minutes, unobservable?
2026-01-02 18:53:18 - 3,191,051t1dP1MJw... receives from the pool+50,000.5541
2026-01-02 19:31:34 - 3,191,091t1U1NE8w... receives from the pool+24,000.9781

The pool is designed to break exactly this link, and it did. What survives it is an amount delta of 0.4059 ZEC, a fifty-two minute gap, a fresh single-use address, and the fact that the same 50,000 ZEC had left that hot wallet eight days earlier. ZECReveal grades that MEDIUM and prints why. It does not say who.

C

In its block

everything a block publishes is exact

This transaction confirmed in block 3,191,051, whose per-pool deltas, coinbase and funding-stream outputs are all public and all exact. A block is the one query on this site with no inference chain on it at all.