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Every tool. One workspace.

rexGST replaces scattered spreadsheets, one-off Python scripts and half a dozen browser tabs with a single reliable toolkit.

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Validation

  • GSTIN validator
    Format + checksum validation for any GSTIN.
  • Bulk GSTIN verifier
    Upload a list, get status for each in one click.
  • PAN ↔ GSTIN extractor
    Derive PAN from GSTIN and vice versa.

Reconciliation

  • GSTR-2A/2B matcher
    Match books vs. portal data with tolerance rules.
  • GSTR-1 vs 3B compare
    Spot mismatches between outward supplies filings.
  • E-invoice reconciler
    Reconcile IRNs against your outward register.

Calculators

  • Interest calculator
    Section 50 interest on delayed payment.
  • Late fee calculator
    GSTR-1, 3B, 9 and 9C late fees.
  • Reverse charge calculator
    RCM applicability + amount.
  • HSN / SAC lookup
    Find rates and descriptions instantly.

Returns & compliance

  • Due-date tracker
    GSTR-1, 3B, CMP-08, 9, 9C and more.
  • Period converter
    Convert quarters, financial years, tax periods.
  • Notice tracker
    Log and follow up on client notices.

Reporting

  • Client dashboard
    See every client's compliance at a glance.
  • Printable reports
    White-labelled PDFs for client sharing.

Utilities

  • State code lookup
    GST state codes and jurisdictions.
  • Rate finder
    Search current GST rates by product/service.

Designed for daily practice

Save 2–4 hrs per day

Handles bulk inputs

Client-ready reports

Regular updates