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FintechToolkit

The AI- and developer-first directory of fintech infrastructure tools. Curated APIs, data sources, and open-source projects for builders shipping payments, banking, and beyond.

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API

44 tools

Tools of this type

Stripe logo

Stripe

Featured

Full-stack payments platform for accepting payments, managing subscriptions, and running marketplaces.

Payments & Billing
API, SDKGlobalUsage-based
Plaid logo

Plaid

Connect bank accounts and access transactions, balances, and identity via one open banking API.

Banking & Open Finance
APIUS, UK, EuropeFree tier
Sardine logo

Sardine

Real-time fraud and compliance platform combining device intelligence and AML screening.

Fraud, Risk & AML
API, PlatformGlobalEnterprise
Alloy logo

Alloy

Identity decisioning for KYC, KYB, and ongoing monitoring across 270+ data sources.

Identity & KYC
API, PlatformGlobalUsage-based
Massive (formerly Polygon.io) logo

Massive (formerly Polygon.io)

Real-time and historical market data for stocks, options, forex, and crypto over low-latency websockets.

Financial Data & Market Data
APIGlobalFree tier
Tink logo

Tink

PSD2-compliant open banking for account aggregation, payment initiation, and finance data.

Banking & Open Finance
API, SDKEuropeUsage-based
Onfido (part of Entrust) logo

Onfido (part of Entrust)

AI-powered identity verification and biometric authentication for global onboarding and KYC.

Identity & KYC
API, SDKGlobalUsage-based
Brex logo

Brex

Spend management and corporate cards API for venture-backed and enterprise companies.

Payments & Billing
APIUSEnterprise
Alpaca logo

Alpaca

Commission-free US stock and crypto trading API for building brokerage and wealth apps.

Investing & Wealth
APIUSFree tier
Unit logo

Unit

Embedded finance platform for adding banking, cards, and lending to any product.

Banking & Open Finance
API, PlatformUSUsage-based
Open Exchange Rates logo

Open Exchange Rates

Reliable, up-to-date currency data and exchange rates API.

Financial Data & Market Data
APIGlobalFree tier
ComplyAdvantage logo

ComplyAdvantage

AI-driven AML and sanctions screening with real-time risk intelligence.

Fraud, Risk & AML
API, PlatformGlobalEnterprise
Adyen logo

Adyen

Featured

Single global platform for card acquiring, local payment methods, and unified commerce.

Payments & Billing
API, PlatformGlobalUsage-based
Checkout.com logo

Checkout.com

Enterprise payment processing with direct acquiring and granular authorisation control.

Payments & Billing
APIGlobalUsage-based
Paddle logo

Paddle

Merchant of record for software companies — billing, sales tax, and compliance handled.

Payments & Billing
API, PlatformGlobalUsage-based
Lemon Squeezy logo

Lemon Squeezy

Merchant of record for digital products, with checkout, subscriptions, and tax handled.

Payments & Billing
APIGlobalUsage-based
Mollie logo

Mollie

European payments provider with local methods and a deliberately simple integration.

Payments & Billing
API, SDKEuropeUsage-based
Razorpay logo

Razorpay

Full-stack payments and business banking for the Indian market.

Payments & Billing
API, SDKIndiaUsage-based
Airwallex logo

Airwallex

Global accounts, FX, and payouts for businesses operating across multiple currencies.

Payments & Billing
API, PlatformGlobalUsage-based
TrueLayer logo

TrueLayer

Open banking payments and data across the UK and Europe, built on PSD2 rails.

Banking & Open Finance
APIEurope, UKUsage-based
GoCardless logo

GoCardless

Bank debit and open banking payments for recurring and invoice collection.

Banking & Open Finance
APIGlobalUsage-based
Yapily logo

Yapily

Open banking infrastructure with no end-user interface — a pure API layer.

Banking & Open Finance
APIEurope, UKUsage-based
Modern Treasury logo

Modern Treasury

Payment operations: ledgering, reconciliation, and bank connectivity in one layer.

Banking & Open Finance
API, PlatformUSEnterprise
Increase logo

Increase

Banking primitives — accounts, ACH, wires, and cards — exposed as a direct API.

Banking & Open Finance
APIUSUsage-based
Column logo

Column

A nationally chartered bank with its own developer API, no intermediary.

Banking & Open Finance
APIUSUsage-based
Treasury Prime logo

Treasury Prime

Embedded banking that connects fintechs directly to partner banks.

Banking & Open Finance
API, PlatformUSEnterprise
Persona logo

Persona

Configurable identity verification and KYB workflows for individuals and businesses.

Identity & KYC
API, PlatformGlobalUsage-based
Veriff logo

Veriff

AI-driven document and biometric verification with broad document coverage.

Identity & KYC
API, SDKGlobalUsage-based
Sumsub logo

Sumsub

Full verification stack — KYC, KYB, AML screening, and transaction monitoring.

Identity & KYC
API, PlatformGlobalUsage-based
Trulioo logo

Trulioo

Global identity and business verification through a single aggregated API.

Identity & KYC
APIGlobalEnterprise
Sift logo

Sift

Machine-learning fraud prevention across payments, accounts, and content abuse.

Fraud, Risk & AML
API, PlatformGlobalEnterprise
Unit21 logo

Unit21

No-code fraud and AML operations — rules, case management, and investigations.

Fraud, Risk & AML
API, PlatformGlobalEnterprise
Chainalysis logo

Chainalysis

Blockchain analytics for crypto AML, sanctions screening, and investigations.

Fraud, Risk & AML
API, PlatformGlobalEnterprise
SEON logo

SEON

Fraud prevention built on digital footprint analysis from email, phone, and IP.

Fraud, Risk & AML
APIGlobalUsage-based
Finnhub logo

Finnhub

Real-time market data, fundamentals, and alternative data with a usable free tier.

Financial Data & Market Data
APIGlobalFree tier
Twelve Data logo

Twelve Data

Stock, forex, and crypto data over REST and websockets, with a generous free tier.

Financial Data & Market Data
APIGlobalFree tier
Financial Modeling Prep logo

Financial Modeling Prep

Fundamentals, statements, and valuation data for equities research tooling.

Financial Data & Market Data
APIGlobalFree tier
Alpha Vantage logo

Alpha Vantage

Free market data API covering equities, forex, crypto, and technical indicators.

Financial Data & Market Data
APIGlobalFree tier
Frankfurter logo

Frankfurter

Open Source

Free, open-source exchange rates API sourced from European Central Bank data.

Financial Data & Market Data
API, OSSGlobalFree
Tradier logo

Tradier

Brokerage and market data APIs for building trading applications.

Investing & Wealth
APIUSUsage-based
DriveWealth logo

DriveWealth

Fractional investing infrastructure for embedding brokerage into other products.

Investing & Wealth
APIGlobalEnterprise
Moov logo

Moov

Open Source

Payments platform with a large set of open-source Go libraries for ACH and wires.

Developer InfrastructurePayments & Billing
API, OSSUSUsage-based
Formance logo

Formance

Open Source

Open-source programmable ledger for modelling money movement in your own stack.

Developer Infrastructure
API, OSSGlobalFree tier
Hyperswitch logo

Hyperswitch

Open Source

Open-source payment orchestrator that routes across multiple processors.

Developer InfrastructurePayments & Billing
API, OSSGlobalFree