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 APIs 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 15 more developer resources.
Kin Score
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
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Postman Collections 9
Ready-to-run Postman collections for exercising this provider's APIs.
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Open Collections 10
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
API Collection
OPEN COLLECTIONTaxJar Sales Tax Categories API
OPEN COLLECTIONTaxJar Sales Tax Categories Customers API
OPEN COLLECTIONTaxJar Sales Tax Categories Nexus API
OPEN COLLECTIONTaxJar Sales Tax Categories Rates API
OPEN COLLECTIONTaxJar Sales Tax Categories Summary Rates API
OPEN COLLECTIONTaxJar Sales Tax Categories Taxes API
OPEN COLLECTIONTaxJar Sales Tax Categories Transactions - Orders API
OPEN COLLECTIONTaxJar Sales Tax Categories Transactions - Refunds API
OPEN COLLECTIONTaxJar Sales Tax Categories Validations API
OPEN COLLECTIONScroll for all 10
Pricing Plans 1
Published pricing tiers and plan structures.
Taxjar Plans Pricing
PLANSRate Limits 1
Documented rate limits and quota policies.
Taxjar Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals for API financial operations.
Taxjar Finops
FINOPSSemantic Vocabularies 1
JSON-LD contexts and semantic vocabularies used across these APIs.
Taxjar Context
JSON-LDSpectral Rules 1
Spectral governance rulesets for linting and validating these APIs.
TaxJar API Rules
SPECTRALJSON Schema 2
Standalone JSON Schema definitions for this provider's data models.
TaxJar Order Transaction
JSON SCHEMATaxJar Tax Calculation Response
JSON SCHEMAExamples 3
Example request and response payloads for these APIs.
Security Posture 3
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
Recommended x-agentic-access execution contracts for AI agents.
Resources
Get Started 1
Portal, sign-up, and the first successful call
Documentation 2
Reference material describing how the API behaves
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Design & Contract 2
Pagination, idempotency, versioning, errors, and events
Build 2
SDKs, sample code, and the tooling you integrate with
Access & Security 3
Authentication, authorization, and security posture
Operate 3
Status, limits, changes, and where to get help
Commercial 3
Pricing, plans, and the legal terms of use
Company 4
The organization behind the API
Other 1
Properties that don't map to a standard resource type
Source (apis.yml)
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