USPS DIM divisor 2026 — 166 → 139 on 2026-07-12

A lower divisor divides the same cubic inches into more pounds, so every bulky-but-light parcel got heavier on 2026-07-12. The trap runs both ways: a June shipment billed at the July divisor is an overcharge you can dispute, and a July shipment billed at 166 means your own cost estimate is still under-quoting.

Audits each line at the divisor in force on its own ship date — 166 before 2026-07-12, 139 from that date.
Accepts the new divisor as billed once it is in force: no false disputes against a correct invoice.
Prices the delta from your contract rate card, in cents, per tracking number.

1 · Your two files

Paste or upload the shipment records you handed over and the carrier's invoice lines. The audit runs in this page — the same deterministic engine the agent tools call.

Shipment records (CSV)Invoice lines (CSV)

Contract rate card (CSV) — optional, and the only way a line gets priced

Shipment records fileInvoice lines fileRate card file

The examples are synthetic worked cases (the same fixtures the build gate asserts against). Your own files are audited in the browser: no upload, no LLM, no third-party call.

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