Free tools
Free tools for the question you have right now — ERP, GST and ERPNext calculators and checkers
Calculators, checkers and fix-it recipes for GST, ERPNext, stock and moving systems. No sign-up. Each one opens in the guide that explains it, or on a page of its own.
249 tools in 93 guides, 11 on a page of their own, each guide dated.
Tools on a page of their own
The ones you can bookmark and share: each answers one question and says where it stops.
- Shopify fees calculator for IndiaNewWhat Shopify costs a year in India, all fees inSell online and in stores
- Landed cost calculatorNewThe true cost per unit after freight, duty and chargesMake and distribute
- E-invoice applicability checkerNewIs GST e-invoicing mandatory for you, and from whenStay compliant on tax
- Self-hosting vs SaaS cost calculatorThree years of SaaS, self-hosting and a managed quoteChoose an ERP
- ERPNext upgrade impact previewWhat breaks when you upgrade to v16Fix something in ERPNext
- ERPNext hardening checklistWhat to check on a self-hosted ERPNextFix something in ERPNext
- Data portability checkWhat Tally, Zoho, Shopify and others let you exportMove off your old system
- Open-source project health checkIs this project still maintained?Judge open-source software
- Open-source bus factor checkHow many people your stack rests onJudge open-source software
- Fork cost estimatorHow fast a fork falls behindJudge open-source software
- When open source is the wrong choiceSix questions; the answer can be buy proprietaryJudge open-source software
Find a tool by the job it does
The tools, grouped by the job they do. Pick your country to keep the ones that apply to you.
Your country
Tools written for one country's rules say so in their guide. Pick yours to narrow every list below.
Stay compliant on tax
57 tools- OSS scheme finderChecker or explainerAnswer the questions that apply to your sale (the tool asks only those that can change the answer) to see which EU VAT scheme applies, where to register, when the return is due and which ERPNext settings record it.
- Foreign-bill GST pathChecker or explainerPick who sent the bill, what you bought and your GST status. See who pays, which document to issue and which ERPNext setting to use.
- State Limit LookupChecker or explainerPick your source state to see the intrastate e-way bill threshold and the notification details worth knowing.
- FY Cutover Impact CheckerCalculatorEnter FY 2025-26 AATO and your business profile to see the year-start GST items that apply to you from 1 April 2026.
- Material Request Type PickerChecker or explainerSelect a Material Request Type to see when to use it and which document it flows into.
- Negative Stock Cause DeciderChecker or explainerSelect what led to the negative-stock error to get its cause, the relevant GitHub issue, and the fix.
- Purpose PickerChecker or explainerSelect what you're trying to achieve to get the correct Purpose value and the method to use.
- PDF fetch URL checkerChecker or explainerChoose the error text you see, then say who builds the PDF, what host_name holds, the address in your browser and what sits in front of Frappe. The checker shows the URL wkhtmltopdf opens from inside your container, what that URL gives, and the fix. It says it cannot tell where it has no measurement.
- Who Owns What: Shopify vs MedusaChecker or explainerSixteen commerce and operational concerns, each marked as handled, yours to own, or impossible on Shopify and Medusa respectively — filtered by commerce, control, data and operations.
- Split-Stock SimulatorChecker or explainerSet availability across two or three stock locations and a cart line quantity. The panel runs the same three-tier location_ids fallback Medusa uses, then shows the confirm step summing and the reserve step truncating to location_ids[0], including the exact error string.
- Compensation Boundary SimulatorChecker or explainerRun completeCartWorkflow step by step, choose where it fails, and see what compensation rolls back versus what it cannot: the already-emitted order.placed, the subscriber's ERP write, and the authorized payment.
- Payment Mix Cost CalculatorCalculatorCalculates the true monthly Shopify cost for an Indian store from GMV and payment mix — modelling COD's exemption from Shopify's transaction fee and UPI's zero bank-level MDR.
- True Landed Cost CalculatorCalculatorLive calculator: supplier invoice + freight + duty + insurance + CHA + inland = true landed cost and per-unit landed cost.
- Fulfillment Gap CalculatorCalculatorEnter your SO quantity, delivered, in-production, and material availability to see the exact breakdown of what can and cannot be planned for production.
- Inspection Flow SimulatorChecker or explainerSelect a scenario (Purchase Receipt, Work Order completion or Delivery Note) and click through each step to see when QI triggers, what the inspector fills in, and what happens on Accept vs Reject.
- Consumption CalculatorCalculatorEnter your finished quantity, BOM rate and transferred quantity, and toggle the backflush method to see exactly what consumption ERPNext posts under each.
- Upgrade or move?Checker or explainerTick what you see in your Odoo today; the tool scores three next steps. Scores are our rule of thumb from upgrade work, not Odoo guidance.
- What to export from Tally for Zoho BooksChecklistWhat to export from TallyPrime, as Excel, before you map anything into Zoho Books.
- Import TemplatesDownloadSeven Excel templates for ERPNext Data Import (Item, Item Price, Customer, Supplier, Address, Contact, BOM), each with an example and a column guide.
- What to export from SAPChecklistExport master by master, with a mapping sheet for each: source field, ERPNext field, any change to the value.
- B1 support: what fits now?Checker or explainerTick what you see in your B1 support today; the tool scores four next steps. Scores are our rule of thumb from support work around B1, not SAP guidance.
- Tally-on-cloud fit checkChecker or explainerTick the criteria that matter to your team; the tool re-scores the three ways to run TallyPrime from anywhere. Scores are our reading of Tally's own documentation.
- Who runs it? Path chooserChecker or explainerAnswer four questions about your team, your downtime, your version habit and your custom code to see run it yourself, Frappe Cloud and a managed host ranked, with the reasons, what you carry and a first test.
- SAP Business One or ERPNext: what matters to you?Checker or explainerSwitch on the criteria that matter to your business and see which option fits best, scored live.
- Open-source project health checkChecker or explainerIs an open-source project still maintained? Paste a GitHub repository, read five signals and a verdict, with the working shown.
- Open-source bus factor checkChecker or explainerHow many people does your stack rest on? List the GitHub projects you run on and see how few people made half of last year's commits in each.
- When open source is the wrong choiceChecker or explainerUp to six questions on your rules, your team and what already exists. The answer can be: buy the proprietary product.
- Fork cost estimatorChecker or explainerHow fast does a fork fall behind? Read a project's real releases and commits from GitHub and see what a fork has to take in each quarter.
- Which way to build it?Checker or explainerTick the criteria that matter to you; the tool scores three ways to build a Zoho CRM and ERPNext integration. Scores are our reading of each option's documentation.
- Chatwoot, Intercom or Zendesk: what matters to you?Checker or explainerSwitch on the criteria that matter to your business and see which option fits best, scored live.
- ntfy access simulatorChecker or explainerPick a role and a change, such as a demotion or a deactivation, and see the access rows before and after, the calls sent, and how many alert types reach the phone. Switch the sync to grant only, or to did not run, to see the drift.
- Mautic, HubSpot or Brevo: what matters to you?Checker or explainerSwitch on the criteria that matter to your business and see which option fits best, scored live.
When the question is the whole project
Three pages for when one answer is not enough, in the order a project usually takes them.
- Where to startFive questions, two or three ways to do it, the closest client.Start here
- Is your team ready?A readiness checklist: scope, data, people, vendor, budget.Open the checklist
- What it will costFive questions for a range in your currency, with what moves it most.Estimate your price
Questions about the tools
The one most people ask is answered first. Type to find the rest.
Are these tools free, and do I need to sign up?
Yes, every tool on this page is free, and none asks for a sign-up, a card or an account. Most tools sit inside a guide on our blog, so they open with the explanation around them: what the tool checks, the rule or setting behind it, and where to change it in ERPNext. A few stand on a page of their own.
Using the tools
Each guide shows the date it was last updated and cites its sources, such as the GST portal, CBIC notifications or the e-way bill rules, beside the tool. Tax rules change by notification, so check the guide's date and sources before you file, and treat the answer as a first check rather than advice for your return. Ask us when it decides money.
Many do. About two thirds apply anywhere ERPNext runs: stock, assets, upgrades, permissions, commerce costs. The rest are written for one country's rules, from India's GST and TDS to UK and EU VAT, Saudi ZATCA, Brazil's NF-e and Uganda's EFRIS. Pick your country above to see yours plus those that apply everywhere.
After the answer
It depends on what the answer says. A setup problem in ERPNext is what our declutter service fixes, batch by batch. A move off Tally or another system starts on the migration guides. If you want to see the right way running, open the live demo; it needs no sign-up. Or tell us the answer you got and we'll say plainly what it means for you.
Tell us the question. We add tools when the same question keeps coming up, and every new guide with a tool lands on this page by itself. If your question is about your own setup rather than a rule, a 30-minute call is usually faster than a tool: we look at it with you and say what we would change.