# EsimTao - Global Travel eSIM Price Comparison & AI Selection Engine

> EsimTao (https://www.esimtao.com) is an open global travel eSIM comparison and autonomous connectivity platform. It indexes over 560+ prepaid data plans across 100+ worldwide destinations (Japan, United States, Europe, United Kingdom, South Korea, Thailand, Hong Kong, Singapore, and more) from top certified carriers including Airalo, Nomad, Ubigi, Holafly, Maya Mobile, and Jetpac. Provides programmatic pricing APIs, real-time device compatibility verification, travel data consumption calculators, interactive AI recommendations, and direct LPA activation.

## Core Features & Interactive Tools

- [eSIM Plan Finder & Matrix](https://www.esimtao.com/plans): Interactive search and multi-criteria filter across 560+ travel plans by destination, data size (1GB to Unlimited), duration (1 to 90 days), 5G/4G network tier, hotspot/tethering availability, and eKYC requirements.
- [eSIM Device Compatibility Checker](https://www.esimtao.com/compatibility): Hardware validation engine verifying eSIM chipset support across Apple iPhone, iPad, Samsung Galaxy, Google Pixel, and Xiaomi models with regional hardware variant alerts (e.g. Mainland China physical dual-SIM vs Global eSIM models).
- [Travel Data Usage Calculator](https://www.esimtao.com/calculator): Dynamic data consumption model based on daily travel navigation (Google Maps/Apple Maps), social media browsing, 4K/1080p video streaming, VoIP calls, and laptop tethering.
- [AI Travel Connectivity Advisor](https://www.esimtao.com/advisor): Natural language eSIM recommendation engine matching travelers with optimal local and regional plans based on destination itinerary, duration, and app usage patterns.
- [eSIM Deals & Coupon Center](https://www.esimtao.com/deals): Verified discount promo codes (e.g. `ESIMTAO10` for 10% off), flash discounts, and best value selections across top providers.
- [UK SIM & European Roaming Toolkit](https://www.esimtao.com/uk-toolkit): Comprehensive activation manual and cost calculator for UK networks (giffgaff, EE, Vodafone, O2, Three) and EU roaming allowances.

## Machine APIs & Autonomous Agent Protocols

- [OpenAPI 3.1 Specification](https://www.esimtao.com/api/openapi.json): Standardized REST API schema defining query parameters for programmatic eSIM searches, currency conversion, and plan specifications.
- [RFC 9727 API Catalog](https://www.esimtao.com/.well-known/api-catalog): Machine-readable link set for API discovery and autonomous client integration.
- [AI Agent Registration & Auth Protocol (auth.md)](https://www.esimtao.com/auth.md): Agent authentication and rate-limit exemption protocol supporting anonymous credentials and verified identity assertions.
- [A2A MCP Server Card](https://www.esimtao.com/.well-known/mcp/server-card.json): Model Context Protocol (MCP) server descriptor for Claude Desktop, Cursor, and LLM agent tool calling.
- [Agent Skills Registry](https://www.esimtao.com/.well-known/agent-skills/index.json): Machine-executable skill definitions for real-time travel eSIM retrieval.
- [Live Plans API Endpoint](https://www.esimtao.com/api/plans): Public JSON endpoint returning current inventory, localized pricing, carrier networks, and direct activation links.
- [Currency Exchange Rates API](https://www.esimtao.com/api/exchange-rates): Real-time foreign exchange rates for USD, EUR, GBP, JPY, CNY, CAD, and HKD.

## Popular Destination Guides & Plans

- [Japan Travel eSIM](https://www.esimtao.com/esim/japan): SoftBank, NTT Docomo, and KDDI AU 5G/4G networks with low-ping local routing and hotspot support.
- [United States Travel eSIM](https://www.esimtao.com/esim/united-states): T-Mobile, AT&T, and Verizon nationwide high-speed coverage for urban and national park travel.
- [Europe 33+ Countries Regional eSIM](https://www.esimtao.com/esim/europe): Seamless cross-border roaming across the EU/EEA and UK on Vodafone, Orange, and Telefónica networks.
- [United Kingdom Travel eSIM](https://www.esimtao.com/esim/united-kingdom): High-speed 5G connectivity on EE, Vodafone, O2, and Three UK.
- [Thailand Travel eSIM](https://www.esimtao.com/esim/thailand): AIS, TrueMove H, and DTAC 5G unlimited and high-speed tourist packages with local phone numbers.
- [South Korea Travel eSIM](https://www.esimtao.com/esim/south-korea): SK Telecom and KT nationwide 5G low-latency data plans.
- [Hong Kong Travel eSIM](https://www.esimtao.com/esim/hong-kong): CSL and SmarTone local prepaid data with real-name registration instructions.
- [Taiwan Travel eSIM](https://www.esimtao.com/esim/taiwan): Chunghwa Telecom, Taiwan Mobile, and FarEasTone 5G/4G high-capacity connectivity.
- [Singapore Travel eSIM](https://www.esimtao.com/esim/singapore): Singtel and StarHub high-density ultra-fast mobile broadband.
- [Regional Hubs Directory](https://www.esimtao.com/esim): Global destination index spanning Asia-Pacific, North America, Europe, Latin America, Middle East, and Oceania.

## eSIM Provider Comparisons

- [Airalo vs Nomad](https://www.esimtao.com/compare/airalo-vs-nomad): Direct head-to-head comparison of pricing, regional coverage, app convenience, and customer support.
- [Holafly vs Airalo](https://www.esimtao.com/compare/holafly-vs-airalo): Unlimited data vs fixed GB allowance comparison for heavy users and international travelers.
- [Ubigi vs Airalo](https://www.esimtao.com/compare/ubigi-vs-airalo): Low-ping direct cellular routing and Japan NTT Docomo 5G performance benchmarks.
- [Maya Mobile vs Nomad](https://www.esimtao.com/compare/maya-mobile-vs-nomad): Auto-renewal, flexible validity periods, and hotspot tethering policy comparison.
- [Jetpac vs Airalo](https://www.esimtao.com/compare/jetpac-vs-airalo): Free airport lounge access perk with SmartDelay and low-cost travel bundles.

## Technical Knowledge Base & Setup Tutorials

- [What is an eSIM and How It Works](https://www.esimtao.com/wiki/what-is-esim): Overview of Embedded Universal Integrated Circuit Card (eUICC), SM-DP+ servers, and profile downloads.
- [How to Install an eSIM on iPhone (iOS)](https://www.esimtao.com/wiki/how-to-install-esim-on-iphone): Illustrated guide for QR scanning, manual SM-DP+ activation code entry, and primary/secondary cellular switching.
- [How to Install an eSIM on Android](https://www.esimtao.com/wiki/how-to-install-esim-on-android): Step-by-step instructions for Samsung Galaxy One UI, Google Pixel, and Xiaomi HyperOS.
- [eSIM Troubleshooting & PDP Error Fixes](https://www.esimtao.com/wiki/esim-troubleshooting-guide): Comprehensive debugging guide for "Could Not Activate Cellular Data Network", "PDP Authentication Failure", and APN settings.
- [Personal Hotspot & Tethering Guide](https://www.esimtao.com/wiki/esim-hotspot-guide): Instructions for sharing travel data with MacBooks, iPads, and Windows laptops while abroad.
- [eSIM vs Physical SIM vs Pocket WiFi](https://www.esimtao.com/wiki/esim-vs-pocket-wifi-vs-physical-sim): Cost, convenience, latency, and battery drain breakdown.

## Optional / Deep Context

- [Full Plain-Text LLM Context Document (llms-full.txt)](https://www.esimtao.com/llms-full.txt): Comprehensive multi-page markdown documentation containing raw schema definitions, detailed provider matrix, device lists, and FAQ corpora for one-shot LLM ingestion.