Practical Business Machines
Open core + hosted precision

The exemptions others miss. The precision you need.

Correct US sales tax by product. Midas gets CA's Prop 163 snack exemption (and every rule like it) right, with a fail-safe that never breaks checkout. Free rooftop-accurate California; hosted precision for every other state, nationwide.

Get started See the matrix

Odoo 19 CE · rooftop California free · multi-state + compliance hosted · flat monthly plans

Live · runs in your browser

California

Tax rate–
Sales tax–
Order total–

CA rates effective 2026-04-01 (CDTFA). For audit-ready tax in all 50 states, use the hosted Midas API.

Why Midas

Tax that respects the product and never surprises the customer.

Midas encodes tax rules the same way states publish them, so it never crashes on promos or charges full rate on CA-exempt snacks, with a fail-safe around the whole engine.

✧

Real categories, real rules

GENERAL, FOOD, FOOD_SNACK, CLOTHING, DIGITAL, SHIPPING, EXEMPT (and more coming). A us.tax.rule says exactly which categories are taxable in which state or *, with citation notes. No magic, no hard-coded exceptions.

🛡️

Fail-safe by design

Any error (bad address, upstream hiccup, unknown category) applies the company fail mode (recommended: fail-open $0 + chatter flag for review). Checkout stays up. No 500s, ever.

📡

Local free + hosted gold

Ships with CA state rates and rules for instant use. Point at the hosted service for county/city/district precision nationwide and always-fresh data. Same contract either way.

The moat

The exemption matrix.

Product taxability is the hard part. One state exempts groceries but taxes candy; another taxes digital but not clothing under a threshold. Midas keeps the matrix as versioned data: rules + citations, not code.

  • CA complete today. Prop 163 snack exemption, standard grocery, apparel, digital, shipping, everything.
  • National by design. Seed from official DOR files (CDTFA, TX Comptroller, SST Rate/Boundary, Tax Foundation). Versioned batches, effective dates, human review for edge cases.
  • Stable codes. Merchants assign a category once on the product. Rules reference the code. Expand later without breaking anything.
us.tax.rule · CA matrixlive
FOOD_SNACK × CA → taxable: false # Prop 163 1992
GENERAL × * → taxable: true
CLOTHING × CA → taxable: true
DIGITAL × * → taxable: true # SaaS / digital goods
EXEMPT × * → taxable: false
# * = catch-all; county overrides via hosted

Works where you sell

Odoo CE, Shopify, anywhere.

The Odoo module is the reference implementation and the free core. The hosted service is a plain JSON API any platform can call. Perfect for side-by-side comparison on real stores that already use TaxCloud.

  • Odoo native. Hooks on sale order confirm + manual recompute on invoices. Reward lines taxed by their own category. Dry, auditable.
  • Shopify parallel. POST /v1/shopify/calculate or /v1/tax with our categories. Compare outputs live with TaxCloud for digital goods and edge jurisdictions, non-destructive refinement loop.
  • Filing assist. /v1/filing_data returns taxable sales by jurisdiction for the period, ready for return prep.
hosted · /v1/tax + parallelrefine
POST /v1/tax
{ origin, destination, lines: [{category:"DIGITAL", amount:29.00}] }
→ { rate:0.0725, amount:2.1025, juris:["CA","Los Angeles"], ... }

Parallel TaxCloud path logs diffs in chatter for data work:
"Our: 7.25% vs TaxCloud: 8.50% | DIGITAL | CA"

Pricing

Free where you start. Paid when you scale.

Rooftop-accurate California is free forever: the Odoo module bundles the full CDTFA rate table and computes on your own server, no API calls. The moment you sell across state lines, the hosted engine adds every other state, always-current rates, and the compliance tier.

Free

$0 · open source (LGPL)

  • Odoo 19 Community module
  • Rooftop-accurate California (500+ jurisdictions, bundled)
  • Product tax categories + exemption matrix
  • Resale certificates + tax ledger
  • Fail-safe engine that never breaks checkout
  • Coupon & reward aware

Starter

$29/mo · up to 500 lookups

  • Everything in Free, plus:
  • Hosted rooftop rates for every US state
  • Always-current data (quarterly refresh)
  • Falls back to bundled CA if offline

Growth

$79/mo · up to 5,000 lookups

  • Everything in Starter, plus:
  • Economic-nexus alerts ($100k / $500k)
  • Exemption-certificate vault
  • Filing-ready reports by jurisdiction

Scale

$149/mo · up to 50,000 lookups

  • Everything in Growth, plus:
  • High-volume throughput
  • Priority support
  • Multi-instance activation

Flat monthly plans, no per-transaction surprises. Best-effort data, not tax advice: you remain responsible for the tax you collect and remit; verify with a qualified tax professional.

Shipped

How Midas got here.

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Square the books

See the right tax on your next order.

We install the module on your CE instance, run your real products and destinations through it, and show you the matrix and the numbers side by side with whatever you use today.

Install request

Leave your address and we write back to run your real products and destinations through the module, side by side with what you use today.

Prefer plain correspondence? hello@practicalbusinessmachines.com