TaxJar

TaxJar is a sales tax automation platform, now a Stripe company, providing APIs for real-time sales tax calculations, rooftop-level rate lookups, transaction recording, and automated filing across US states and international jurisdictions. The platform supports e-commerce businesses of all sizes with sub-20ms response times, 99.999% historical uptime, and AI-powered product tax classification. TaxJar handles nexus tracking, exemption certificate management, and AutoFile returns so merchants can stay compliant without manual effort. Official client libraries are available for Ruby, Python, PHP, Node.js, C#/.NET, Java, and Go.

TaxJar publishes 9 API contracts indexed on the APIs.io network, including Categories API, Customers API, Nexus API, and 6 more. Tagged areas include Sales Tax, Tax Compliance, E-Commerce, Tax Calculation, and Tax Automation.

The TaxJar catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

TaxJar’s developer surface includes authentication, documentation, API reference, engineering blog, pricing, support, signup flow, and 16 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

44.6/100 developing ▬ flat Agent 24/100 agent aware Front door AI 2/6 trace saas Full breakdown ↓
scored 2026-10-23 · rubric v0.25.0 · Show this score on your site →

AccessPaid

1 published contract

Sales Tax Tax Compliance E-Commerce Tax Calculation Tax Automation Stripe Fintech Tax

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Tax Management

BC-220

CategoriesNexusRatesSummary RatesTaxesTransactions - Orders

POST /taxes GET /rates/{zip} POST /transactions/orders GET /nexus/regions

Kin Score

Kin Score How this is scored →
scored 2026-10-23 · rubric v0.25.0

Composite quality — 44.6/100 · developing

Contract Quality 12.8 / 19

Developer Ergonomics 5.5 / 15

Access Clarity 5.5 / 15

Operational Transparency 2.3 / 10

Contract Governance 2.1 / 9

Discoverability 5.0 / 8

Regulatory Posture 3.2 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 24/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

Show this score on your site.

It updates itself when the score changes. Paste this where you link to your API docs:

<a href="https://apis.io/providers/taxjar/"><img src="https://apis.io/badge/taxjar/card.svg" alt="TaxJar on APIs.io — Kin Score by API Evangelist"></a>

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Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/taxjar: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
Commerce Platform Ecosystems (Shopify, WooCommerce, Stripe Apps)	undeclared	-	-	-
E-invoicing and Tax Compliance (certified operators)	undeclared	-	-	-
MACH & Headless Commerce	undeclared	-	-	-
Amazon Seller Ecosystem (Selling Partner Appstore, Amazon Ads partners)	undeclared	-	-	-
E-commerce Extension Marketplaces (Adobe Commerce / Magento, Shopware)	undeclared	-	-	-

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

APIs 9

Individual APIs this provider publishes, each with its own machine-readable definition.

TaxJar Categories API

Product tax categories

TaxJar Customers API

Customer exemption management

TaxJar Nexus API

Nexus region tracking

TaxJar Rates API

Sales tax rate lookups

TaxJar Summary Rates API

Summarized sales tax rates by region

TaxJar Taxes API

Sales tax calculation

TaxJar Transactions - Orders API

Order transaction management

TaxJar Transactions - Refunds API

Refund transaction management

TaxJar Validations API

Address and VAT validation

Scroll for all 9

Postman Collections 9

Ready-to-run Postman collections for exercising this provider's APIs.

TaxJar Sales Tax Categories API

POSTMAN

TaxJar Sales Tax Categories Customers API

POSTMAN

TaxJar Sales Tax Categories Nexus API

POSTMAN

TaxJar Sales Tax Categories Rates API

POSTMAN

TaxJar Sales Tax Categories Summary Rates API

POSTMAN

TaxJar Sales Tax Categories Taxes API

POSTMAN

TaxJar Sales Tax Categories Transactions - Orders API

POSTMAN

TaxJar Sales Tax Categories Transactions - Refunds API

POSTMAN

TaxJar Sales Tax Categories Validations API

POSTMAN

Scroll for all 9

Open Collections 9

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

TaxJar Sales Tax Categories API

OPEN COLLECTION

TaxJar Sales Tax Categories Customers API

OPEN COLLECTION

TaxJar Sales Tax Categories Nexus API

OPEN COLLECTION

TaxJar Sales Tax Categories Rates API

OPEN COLLECTION

TaxJar Sales Tax Categories Summary Rates API

OPEN COLLECTION

TaxJar Sales Tax Categories Taxes API

OPEN COLLECTION

TaxJar Sales Tax Categories Transactions - Orders API

OPEN COLLECTION

TaxJar Sales Tax Categories Transactions - Refunds API

OPEN COLLECTION

TaxJar Sales Tax Categories Validations API

OPEN COLLECTION

Scroll for all 9

Pricing Plans 1

Published pricing tiers and plan structures.

Taxjar Plans Pricing

2 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Taxjar Rate Limits

1 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Taxjar Finops

FINOPS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Taxjar Context

9 classes · 53 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

TaxJar — jsonschema rules

5 rules · 4 warnings 1 info

SPECTRAL

JSON Schema 2

Standalone JSON Schema definitions for this provider's data models.

TaxJar Order Transaction

20 properties

JSON SCHEMA

TaxJar Tax Calculation Response

1 properties

JSON SCHEMA

Examples 3

Example request and response payloads for these APIs.

Calculate Tax Request

13 fields

EXAMPLE

Calculate Tax Response

1 fields

EXAMPLE

Create Order Request

17 fields

EXAMPLE

Security Posture 3

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Taxjar Authentication

http · 1 scheme

SECURITY

Taxjar Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Taxjar Trust Center

SOC 2, GDPR

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Taxjar Agentic Access

22 operations · 11 acting

AGENTIC

Resources

Get Started 1

Portal, sign-up, and the first successful call

Signup

Signup

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Design & Contract 2

Pagination, idempotency, versioning, errors, and events

Vocabulary

Vocabulary

JSONLDContext

JSONLDContext

Build 2

SDKs, sample code, and the tooling you integrate with

PostmanWorkspace

PostmanWorkspace

GitHubOrganization

GitHubOrganization

Access & Security 3

Authentication, authorization, and security posture

TrustCenter

TrustCenter

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 3

Status, limits, changes, and where to get help

StatusPage

StatusPage

Support

Support

RateLimits

RateLimits

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

Plans

Plans

FinOps

FinOps

Company 4

The organization behind the API

Website

Website

LinkedIn

Blog

Blog

BlogFeed

BlogFeed

Other 2

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Source (apis.yml)

aid: taxjar
name: TaxJar
description: TaxJar is a sales tax automation platform, now a Stripe company, providing APIs for real-time sales tax calculations,
  rooftop-level rate lookups, transaction recording, and automated filing across US states and international jurisdictions.
  The platform supports e-commerce businesses of all sizes with sub-20ms response times, 99.999% historical uptime, and AI-powered
  product tax classification. TaxJar handles nexus tracking, exemption certificate management, and AutoFile returns so merchants
  can stay compliant without manual effort. Official client libraries are available for Ruby, Python, PHP, Node.js, C#/.NET,
  Java, and Go.
type: Index
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: paid
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Paid
  confidence: medium
  source:
  - plans
  - authentication
  - security
  generated: '2026-09-03'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/taxjar.png
tags:
- Sales Tax
- Tax Compliance
- E-Commerce
- Tax Calculation
- Tax Automation
- Stripe
- Fintech
- Tax
tags_raw:
- Sales Tax
- Tax Compliance
- E-Commerce
- Tax Calculation
- Tax Automation
- Stripe
- FinTech
- Tax
url: https://raw.githubusercontent.com/api-evangelist/taxjar/refs/heads/main/apis.yml
created: '2026-06-12'
modified: '2026-06-12'
specificationVersion: '0.23'
apis:
- aid: taxjar:taxjar-categories-api
  name: TaxJar Categories API
  description: Product tax categories
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Categories
  properties:
  - type: OpenAPI
    url: openapi/taxjar-categories-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-customers-api
  name: TaxJar Customers API
  description: Customer exemption management
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Customers
  properties:
  - type: OpenAPI
    url: openapi/taxjar-customers-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-nexus-api
  name: TaxJar Nexus API
  description: Nexus region tracking
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Nexus
  properties:
  - type: OpenAPI
    url: openapi/taxjar-nexus-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-rates-api
  name: TaxJar Rates API
  description: Sales tax rate lookups
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Rates
  properties:
  - type: OpenAPI
    url: openapi/taxjar-rates-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-summary-rates-api
  name: TaxJar Summary Rates API
  description: Summarized sales tax rates by region
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Summary Rates
  properties:
  - type: OpenAPI
    url: openapi/taxjar-summary-rates-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-taxes-api
  name: TaxJar Taxes API
  description: Sales tax calculation
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Tax
  tags_raw:
  - Taxes
  properties:
  - type: OpenAPI
    url: openapi/taxjar-taxes-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-transactions-orders-api
  name: TaxJar Transactions - Orders API
  description: Order transaction management
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Transactions - Orders
  properties:
  - type: OpenAPI
    url: openapi/taxjar-transactions-orders-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-transactions-refunds-api
  name: TaxJar Transactions - Refunds API
  description: Refund transaction management
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Transactions - Refunds
  properties:
  - type: OpenAPI
    url: openapi/taxjar-transactions-refunds-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
- aid: taxjar:taxjar-validations-api
  name: TaxJar Validations API
  description: Address and VAT validation
  humanURL: https://developers.taxjar.com/api/reference/
  baseURL: https://api.taxjar.com/v2/
  tags:
  - Validations
  properties:
  - type: OpenAPI
    url: openapi/taxjar-validations-api-openapi.yml
  - type: Documentation
    url: https://developers.taxjar.com/api/reference/
  - type: Guides
    url: https://developers.taxjar.com/api/guides/
  - type: Sandbox
    url: https://api.sandbox.taxjar.com/v2/
  - type: JSONSchema
    url: json-schema/taxjar-order-schema.json
  - type: JSONSchema
    url: json-schema/taxjar-tax-calculation-schema.json
common:
- type: CapabilityMap
  url: capabilities/taxjar-capability-edges.yml
  name: TaxJar Business Capability Map
- type: PostmanWorkspace
  url: https://www.postman.com/kinlaneapi/taxjar/overview
- type: AgenticAccess
  url: agentic-access/taxjar-agentic-access.yml
- type: TrustCenter
  url: security/taxjar-trust-center.yml
- type: DomainSecurity
  url: security/taxjar-domain-security.yml
- type: Authentication
  url: authentication/taxjar-authentication.yml
- type: Website
  url: https://www.taxjar.com
- type: Documentation
  url: https://developers.taxjar.com/
- type: APIReference
  url: https://developers.taxjar.com/api/reference/
- type: GitHubOrganization
  url: https://github.com/taxjar
- type: LinkedIn
  url: https://www.linkedin.com/company/taxjar
- type: Blog
  url: https://developers.taxjar.com/blog/
- type: Pricing
  url: https://www.taxjar.com/pricing/
- type: StatusPage
  url: https://status.taxjar.com
- type: X
  url: https://x.com/taxjardev
- type: Support
  url: https://support.taxjar.com/category/233-taxjar-api
- type: Signup
  url: https://app.taxjar.com/api_sign_up/
- type: Plans
  url: plans/taxjar-plans-pricing.yml
- type: RateLimits
  url: rate-limits/taxjar-rate-limits.yml
- type: FinOps
  url: finops/taxjar-finops.yml
- type: Vocabulary
  url: vocabulary/taxjar-vocabulary.yml
- type: JSONLDContext
  url: json-ld/taxjar-context.jsonld
- type: BlogFeed
  url: blogs/blogs.json
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
x-status: acquired
x-acquired-by: stripe
x-parent: stripe
x-acquired-date: 2021-04
x-status-source: https://www.taxjar.com/blog/taxjar-will-be-joining-stripe-to-help-build-the-worlds-tax-compliance-infrastructure
x-status-evidence: Stripe acquired TaxJar in April 2021; TaxJar runs as a Stripe company and its API is live (roadmap#816)

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