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EN/DE
Live
CoinbaseCoinbase
+
EthereumEthereum
+
GermanyGermany

Crypto tax classification API

Tax data and logic layer for wallets, exchanges, and tax firms. Explainable. Audit-ready. Jurisdiction-aware.

Request pilotSee how it works
terminal

# Classify a wallet

$ taxmaxi classify 0x1a2b... --jurisdiction DE

> Processing 847 transactions...

> 412 tax events classified

> Audit trail: ./output/audit.json

api response
200 OK
{
  "tx_hash": "0x8f2e...3d91",
  "block": 19847231,
  "timestamp": "2024-03-15T14:32:01Z",
  "source": "ethereum_mainnet",
  "protocol": "uniswap_v3",
  "event_type": "SWAP",
  "asset_in": { "symbol": "ETH", "amount": "1.5" },
  "asset_out": { "symbol": "USDC", "amount": "2847.50" },
  "gas_eth": "0.0042",
  "classification": {
    "tax_event": "DISPOSAL",
    "jurisdiction": "DE",
    "method": "FIFO",
    "rule_ref": "EStG_§23",
    "holding_period_days": 412,
    "treatment": "LONG_TERM_EXEMPT"
  },
  "lot_match": {
    "acquired": "2023-01-28",
    "cost_basis_eur": "1823.40"
  },
  "explanation": "Holding period >1yr. Exempt under §23 EStG."
}
REST API + CLI
Full audit trails
DAC8-ready

The Problem

Consumer tax tools were not built for platforms

Consumer tools

Transactions imported1,247
Auto-classified612
Needs manual review635 (51%)
  • Half transactions marked "Unknown"
  • No API access for integration
  • No audit trail or explanation
  • Built for manual CSV uploads

TaxMaxi

Transactions processed847
Classified with audit trail847 (100%)
Tax events generated412
  • Every event includes rule + reasoning
  • REST API for programmatic access
  • Full audit trail for compliance
  • Built for integration

DAC8 + MiCA

European crypto regulation increases compliance requirements. Platforms need infrastructure.

Rising complexity

DeFi, staking, bridges. On-chain activity is too complex for manual classification.

API gap

Tax firms and platforms need APIs. Existing tools are consumer-only.

The Product

Classification infrastructure with full explainability

Raw blockchain and exchange data in. Tax-classified events with audit trails out.

Ingest

Connectors

Coinbase APIETH RPC

Normalize

Unified Schema

EventsMovements

Classify

Tax Engine

RulesLot Match

Apply Law

Jurisdiction

DE (live)US (Q2)

Output

Audit-Ready

APIReports

Every classification is explainable

Drill into any tax event. See the rule applied, the evidence, and the reasoning path.

Event Inspector
evt_8f2e3d91

Transaction

TX Hash0x8f2e...3d91
Block19,847,231
Timestamp2024-03-15 14:32:01 UTC
ProtocolUniswap V3
ActionSWAP
Asset In1.5 ETH
Asset Out2,847.50 USDC
Gas0.0042 ETH

Classification

RULE APPLIED

EStG §23 - Crypto Disposal

Private disposal transaction under German tax law

Classification path:

Swap detectedETH disposedTax event: DISPOSAL

FIFO Lot Match

Acquired2023-01-28
Cost basis1,823.40 EUR
Holding period412 days
Tax treatmentLONG_TERM_EXEMPT

Holding period exceeds 1 year. Gain of 1,024.10 EUR is tax-exempt under §23 EStG.

API-first

RESTful API with webhooks. Stream classified events in real-time. Build tax features into your product.

POST /v1/wallets/{address}/classify
{
  "jurisdiction": "DE",
  "method": "FIFO"
}

Deterministic

Same input, same output. Every classification includes the rule reference and reasoning. Fully auditable.

{
  "rule_ref": "EStG_§23",
  "classification_path": [...],
  "audit_id": "aud_x8k2m"
}

Jurisdiction-aware

German tax law live now. US and UK planned for Q2-Q4 2026. One API, jurisdiction as a parameter.

{
  "live": ["DE"],
  "planned": ["US", "UK", "FR"],
  "methods": ["FIFO", "LIFO"]
}

AI-Ready Architecture

Structured for machine consumption

Tax copilots and AI agents need structured, explainable data. TaxMaxi outputs include rule references, reasoning paths, and plain-language explanations that LLMs can relay directly.

Inspectable reasoning

Every classification includes the rule applied (e.g. EStG §23), the lot match used, and the reasoning path from transaction to tax event.

Deterministic outputs

Same input, same output. No probabilistic classification. AI systems can trust the data and explain it to users with confidence.

Structured JSON

Clean field semantics. No PDF parsing or HTML scraping. Direct integration with any AI system or copilot.

Classification Schema
v1.0

INPUT

tx_hash:string
0x8f2e...3d91
source:string
ethereum_mainnet
jurisdiction:string
DE

PROCESSING

Parse transaction
Match against rule set
FIFO lot matching
Apply jurisdiction rules

OUTPUT

tax_event:string
DISPOSAL
rule_ref:string
EStG_§23
treatment:string
LONG_TERM_EXEMPT
holding_period_days:number
412
explanation:string
Holding >1yr, exempt under §23

LLM-ready: The explanation field provides natural language reasoning that AI systems can relay directly to end users.

Roadmap

Coverage expansion

Starting focused. Expanding based on customer demand.

Q1 2026

Live

Exchanges

Coinbase

Chains

Ethereum

Jurisdictions

Germany

Q2 2026

In development

Exchanges

Kraken

Chains

Bitcoin
Solana

Jurisdictions

United States

Q3-Q4 2026

Planned

Jurisdictions

United Kingdom
France

Roadmap reflects current plans. Timelines may shift based on demand and regulatory changes.

Pricing

Infrastructure pricing

We work with partners through structured pilots. Pricing scales with transaction volume.

Pilot

Evaluate with real data

Freepilot period
  • Up to 1,000 transactions
  • Full API access
  • Germany jurisdiction
  • Direct founder support
Request pilot

Growth

Per-transaction pricing

Customvolume-based
  • Unlimited transactions
  • Full API + webhooks
  • Multi-jurisdiction (as available)
  • Volume discounts
  • SLA included
Get pricing

Enterprise

Annual agreement

Contactcustom terms
  • Everything in Growth
  • Dedicated support
  • Custom integrations
  • On-premise option
  • Compliance review
Contact us

All engagements start with a pilot. Full API documentation and integration support included.

Use Cases

Built for platforms, not consumers

Your product, your UX. TaxMaxi provides the classification layer.

Tax Firms

Primary focus

Germany first

API-driven classification for client portfolios. Replace manual spreadsheet work with programmatic processing and audit-ready outputs.

POST /v1/batch/classify
{
  "wallets": ["0x1a2b...", "0x3c4d..."],
  "jurisdiction": "DE"
}

Wallets

Embed tax features

Real-time tax estimates inside your wallet. Pre-trade tax preview. Year-end summaries. Turn compliance into a feature.

GET /v1/wallets/{address}/summary
{
  "year": 2025,
  "jurisdiction": "DE"
}

Exchanges

Compliance infrastructure

DAC8 reporting requirements. Per-user tax statements. Jurisdiction-aware classification without building the logic yourself.

POST /v1/reports/dac8
{
  "user_id": "usr_abc123",
  "period": "2025"
}

Neobanks

Crypto tax module

Add crypto tax compliance without building classification infrastructure. Managed jurisdiction updates as laws change.

GET /v1/portfolios/{id}/tax-events
{
  "jurisdiction": "DE",
  "method": "FIFO"
}
MA

Max Ast

Founder

Software engineer. Filed crypto taxes across 50+ protocols and saw how broken the tooling is. Building the infrastructure that should exist.

Berlin-based50+ protocols filed