Knowledge Resources

Open Reference Library

Verified reference guides, checklists, and research notes across contracts, tax, procurement, and compliance — sourced from Acts, Rules, and official notifications. Free to read.

Resource Categories

Browse the Library by Topic

Every resource is verified from primary sources — Acts, Rules, judgments, and official government notifications.

Contracts & Claims

Reference guides for the Indian Contract Act, FIDIC, GCC, EOT, force majeure, and claims management in EPC projects.

Income Tax Reference

Deduction tables, TDS rate charts, advance tax schedules, ITR form selection guides — from the Income Tax Act and Finance Acts.

GST Reference

GSTR filing calendars, e-invoicing thresholds, ITC rules, and HSN/SAC rate schedules from CGST Act and CBIC notifications.

Procurement Reference

GFR 2017 rules, GeM Portal guidance, CVC guidelines, and public procurement checklists for government and PSU projects.

Business Compliance

MSME/Udyam registration guides, Companies Act compliance calendars, labour law summaries, and sectoral registration guides.

Checklists & Glossaries

Contract review checklists, compliance calendars, and plain-language glossaries for legal and commercial terms.

Guides in development — publishing soon.

Interactive Tools

Free Calculators and Lookup Tools

Tools built from the same verified sources as the guides — no sign-up required.

Income Tax Calculator

Old vs New Regime comparison for FY 2024-25. Verified against Finance Act 2024.

HSN/SAC Code Finder

GST rates for any product or service using the CBIC tariff schedule. Search by keyword or browse by chapter.

All Calculators

Browse the full HaritaZen calculator library — tax, financial, and compliance tools.

Knowledge Grounded in Primary Sources

Every guide and calculator in the HaritaZen library is verified from Acts, Rules, and official government notifications — not paraphrased from secondary sources.