tools

calculate_fiduciary_tax

Compute US federal income tax for an ESTATE or TRUST (Form 1041): the § 1(e) compressed brackets and § 642(b) exemption. Input is taxable income before the exemption, after the §§ 651/661 distribution deduction. Retained capital gains refuse loudly (§ 1(h) trust breakpoints not modeled). Grantor trusts belong on the grantor's individual return via calculate_tax.

post/v1/tools/calculate_fiduciary_tax

Request

  • Base URL: https://opentax.invaro.ai
  • URL: https://opentax.invaro.ai/v1/tools/calculate_fiduciary_tax
  • Auth: one of:
    • HTTP bearer
    • none

Headers

X-OpenTax-Return-Idstring

Your identifier for the taxpayer-year this call belongs to; the billing unit. Stored hashed.

Request body

fiduciaryType'estate' | 'simple-trust' | 'complex-trust'

Form 1041 filer type for the § 642(b) exemption: estate ($600), simple trust required to distribute all income currently ($300), or complex trust ($100). Grantor trusts do not file their own tax — use the grantor's individual return.

targetstring

rule to derive (default: us.federal.fiduciary.income_tax).

asOfstring

REQUIRED for computation: the law-in-force date — use the intended tax year's year-end (e.g. "2025-12-31" for TY2025). Omitting it is an error, never a default.

includeProofboolean

include the full proof artifact in the response as proof (PROOF-FORMAT v2: every applied rule, input, assumption and rounding, verifiable offline against corpusMerkleRoot; ~200 KB). Default false — the hashes alone are returned.

Response

ok:true with the computed value, line set or lookup hits; ok:false with error.code when the engine refuses (NEEDS_FACTS, NO_APPLICABLE_RULE, UNHANDLED_ENUM_CASE)

okboolean required

Changes

No recorded changes to this operation across all 1 revision of this API.