Pph21 Calculator

PPh 21 TER Hybrid Tax Calculator

A hybrid precision engine for calculating employee PPh 21 monthly taxes (Jan-Nov) and December annual reconciliation.

Statutory Provenance

• Primary Regulation: Peraturan Pemerintah (PP) No. 58 Tahun 2023 & Peraturan Menteri Keuangan (PMK) No. 168 Tahun 2023.
• Effective Date: January 1, 2024.
• Authority: Direktorat Jenderal Pajak (DJP), Kementerian Keuangan RI.

Execution Model (Hybrid Engine)

Do not perform mathematical computations using the probabilistic LLM. Instead, extract parameters and feed them to the deterministic engine (engines/pph21-calculator.js).

1. Monthly Withholding (Jan-Nov)

• Match PTKP to TER Category:
  • Category A: TK/0 (54M), TK/1 (58.5M), K/0 (58.5M).
  • Category B: TK/2 (63M), TK/3 (67.5M), K/1 (63M), K/2 (67.5M).
  • Category C: K/3 (72M).
• Multiply gross monthly salary by matched bracket rate.
• Apply 20% penalty if hasNpwp is false or NIK is not validated.

2. December Annual Reconciliation (Masa Pajak Terakhir)

• Determine PTKP threshold deduction.
• Deduct Biaya Jabatan (5% of gross, capped at Rp 500.000/month or Rp 6.000.000/year).
• Deduct employee BPJS JHT (2%) and JP (1%).
• Compute progressive Article 17 progressive tax on Net Taxable Income (PKP):
  • Up to Rp 60M: 5%

  • Rp 60M to Rp 250M: 15%

  • Rp 250M to Rp 500M: 25%

  • Rp 500M to Rp 5B: 30%

  • Above Rp 5B: 35%
• Subtract tax already withheld during Jan-Nov to yield December tax.

Standardized Output Schema

Ensure output matches the following structure:

### PPh 21 Tax Calculation Report

#### Parameter Summary
* **Monthly Gross Salary / Annual**: Rp [Amount]
* **PTKP Status**: [Status]
* **Identity Validation**: [validated_nik_npwp / unvalidated] (Penalty applied: [Yes/No])

#### Calculation Details
* **Tax Period**: [Jan-Nov / December Reconciliation]
* **Tax Withheld**: Rp [Amount]
* **Regulatory Authority**: DJP RI

Trust Envelope (Confidence Contract)

Every engine output must be wrapped in a structured envelope declaring production trust attributes:

• regulatory_framework: Applying regulation with article references (e.g. PP No. 58/2023 jo. PMK 168/2023 - TER).
• ruleset_version: Versioned Id of the engines/rules/*.json ruleset consulted (e.g. PPH21-2024 v1.0.0).
• effective_window: [effective_from] – [effective_to] of the applied ruleset.
• integrity_status: VERIFIED after SHA-256 ruleset check, or UNVERIFIED — never present silent calculations when UNVERIFIED.
• risk_level: Contextual LOW / MEDIUM / HIGH per skill risk metadata.
• requires_human_review: true for HIGH risk outputs — mandatory professional sign-off before filing, payment, or execution.
• currency: IDR, rounded to the nearest whole Rupiah unless another precision is stated.
• as_of: The simulation/effective date used to select the ruleset.