New User Offer Get $5 free credit instantly — no credit card required. Use code WELCOME Claim $5 Free
Developer-First API Platform

Build Faster with
CoreNexis APIs

Production-ready APIs for email validation, image CDN, PDF OCR, QR generation, format conversion and more. Start free, scale with confidence.

RESTful
Free Tier
TLS Encrypted
Auto-Scaling
D R S A +
Trusted by 12,000+ developers worldwide
POST
0%
Average Uptime
0+
API Services
0K+
Developers Trust Us
0+
Languages Supported
API Collection

Powerful APIs, Ready to Integrate

From email verification to PDF OCR and image hosting, explore our growing suite of production-ready APIs. Every API includes a free tier.

Stable

Markdown to PDF API

Turn Markdown into a clean, print-ready PDF or page images. Tables, task lists and syntax highlighted code all render correctly, with thirteen typefaces, a full colour palette and complete control over page size, orientation and margins. Documents of a thousand pages and more are handled, and every result comes back as a hosted link.

  • Tables and Task Lists
  • Syntax Highlighted Code
  • 13 Fonts and Custom Colours
  • PDF or PNG Output
Starts at Free
Docs
Stable

HTML to PDF API

Render HTML and CSS exactly as a browser does and take it away as a PDF or as page images. Grid, flexbox, gradients and web fonts all work, with optional JavaScript execution and full control over page size, margins and scale. A long document comes back as an ordered sequence of images rather than one that stops partway down.

  • Full Modern CSS
  • Grid and Flexbox
  • JavaScript Execution
  • PDF or Page Images
Starts at Free
Docs
Stable

Image to Text (OCR) API

Convert any image into clean text and markdown using advanced OCR. Send a photo, screenshot, scan, bill or signage and get the text back instantly, with automatic language detection across 30+ languages.

  • 30+ Languages
  • Auto Language Detection
  • Markdown Output
  • Instant Synchronous Response
Starts at Free
Docs
Stable

PDF to Text (OCR) API

Convert any PDF into clean text and markdown using advanced OCR. Supports scanned PDFs, images, tables and complex layouts with high accuracy across 30+ languages.

  • 30+ Languages
  • Advanced OCR
  • Markdown Output
  • Page Selection
Starts at Free
Docs
Stable

Email Validator API

Real-time email verification with DNS checks, disposable detection, MX records and quality scoring to keep your lists clean.

  • Real time SMTP & catch all verification
  • Email syntax & deliverability check
  • Disposable email detection
  • MX, SPF & DMARC validation
  • Quality & confidence scoring
Starts at Free
Docs
Stable

Image CDN API

Upload, store and deliver images via a global CDN with flexible storage durations and social sharing built in.

  • Upload via file or URL
  • Multiple storage duration options
  • Fast global CDN delivery
  • Image viewer & social sharing
Starts at Free
Docs
Available

QR Code & Barcode API

Generate QR codes, UPI payment QRs and barcodes with logo embedding. Supports Code128, EAN-13 and UPC-A.

  • UPI QR - GPay, PhonePe, Paytm
  • Standard QR for any data
  • Code128, EAN-13, UPC-A barcodes
  • Image-to-QR code generation
Starts at Free
Docs
Stable

Image Conversion API

Auto-detect and convert images across 25+ formats, any format to any format. Modern codecs including AVIF, HEIC and JPEG XL, correct colour handling for CMYK and transparency, and animations that stay animated.

  • Automatic format detection
  • JPG, PNG, WebP, AVIF, HEIC, JPEG XL & more
  • Dynamic resize & quality control
  • Animated GIF and WebP preserved
Starts at Free
Docs
Stable

Disposable Email Detector API

Detect disposable, temporary and fake email addresses in real time. Block spam signups and protect your platform with a fast, accurate and lightweight API.

  • Prevent fake accounts and spam registrations
  • 146k+ disposable domain database
  • Easy integration with any platform
  • Industry-leading spam & fraud accuracy
Starts at Free
Docs

Need a Custom Plan?

Looking for higher limits, dedicated infrastructure or a tailored solution for your team? Let us build a plan that fits your exact needs.

Quick Start

Integrate in a Few Lines

Authenticate with a single header and start making requests. Pick your language and copy the snippet.

1

Create your free key

Sign up and generate an API key from the dashboard in seconds.

2

Send the header

Pass your key as the X-API-Key header on every request.

3

Read the JSON

Every endpoint returns clean, predictable JSON with clear status codes.

Get Your API Key
Quick Start

Go Live in Minutes

From sign-up to production in just a few steps.

1

Sign Up Free

Create an account and get your API key instantly.

2

Pick an API

Browse the collection and read detailed docs.

3

Integrate

Copy and paste code examples into your app.

4

Test

Use the free tier to test thoroughly with real data.

5

Go Live

Switch to production and monitor from the dashboard.

Use Cases

Built for Real Products

Drop CoreNexis APIs into the workflows your product already needs.

User Onboarding

Validate emails at signup to block fake and disposable accounts before they enter your funnel.

E-commerce Media

Host product images on a global CDN and convert uploads to optimized WebP or AVIF on the fly.

Payments & UPI

Generate UPI payment QRs and standard barcodes for checkout, invoices and point of sale.

Document Processing

Turn scanned PDFs into searchable text and markdown for automation and data pipelines.

Marketing & CRM

Clean mailing lists in bulk, improve deliverability and protect your sender reputation.

Fraud Prevention

Detect temporary mail domains in real time to stop spam, abuse and fake registrations.

Developer Experience

Why Developers Choose Us

Built with simplicity, performance and great documentation at the core.

Clear Documentation

Comprehensive guides with code examples in multiple languages.

High Performance

Distributed edge architecture with low latency and high availability.

Security First

TLS encryption, token auth and regular security audits.

Versioned APIs

Backward compatible, so your integrations will not break.

Manual Review

Every request reviewed for secure and ethical usage.

99.9%+ Uptime

Resilient infrastructure running smoothly 24/7.

Plug & Play

Copy-paste-ready snippets and intuitive endpoints.

Dev Support

Dedicated support channels on paid plans.

Integration

Works With Any Stack

Language-agnostic APIs that integrate with any platform supporting HTTP.

JavaScript
Python
PHP
Java
Ruby
cURL
Swift
Model Context Protocol

Every API, inside your AI agent

One server address turns all 9+ CoreNexis APIs into tools Claude, n8n or any agent can call — using the same API key you already have.

Nothing to install

No package, no separate process. Paste one address into your client and the tools appear.

Your existing key

Same key, same plans, same quotas. A tool call is one REST call, billed exactly as it is today.

Just ask

“Turn this Markdown into a PDF”, “read the text out of this image”, “check these email addresses”.

markdown_to_pdf html_to_pdf image_to_text pdf_to_text email_validate image_convert image_cdn_upload qr_barcode_generate +6 more
claude_desktop_config.json
{
  "mcpServers": {
    "corenexis": {
      "type": "http",
      "url": "https://api.corenexis.com/mcp/server",
      "headers": {
        "x-api-key": "YOUR_API_KEY"
      }
    }
  }
}
Operational Streamable HTTP · works with Claude, n8n and any MCP client

Ready to Power Your Applications?

Start with the free tier to explore, then scale as you grow. Flexible pricing, so you only pay for what you use.

Start Building Free
FAQ

Frequently Asked Questions

Quick answers to common questions about our APIs.

What programming languages are supported?
Our APIs are language-agnostic and work with any language that supports HTTP requests. We provide code examples in JavaScript, Python, PHP, Ruby, cURL and more.
Are there rate limits on API calls?
Yes, each plan has its own rate limit. Free plans have lower limits while paid plans offer much higher throughput. Check each API's pricing for specifics.
Is there a Service Level Agreement (SLA)?
Yes, paid plans include SLAs. Standard plans include 99.9% uptime, while Agency and Enterprise plans offer higher uptime targets with priority support.
Can I test APIs before purchasing?
Absolutely. Every API has a free tier you can use for testing and development, so you can try real data before committing to a paid plan.
How do I handle API errors?
All APIs use standard HTTP status codes and return detailed JSON error messages. Our documentation includes a comprehensive error reference guide.
Do you provide technical support?
Dedicated email support is available on paid plans. Free tier users have access to detailed documentation. For API-specific questions, feel free to reach out anytime.

Stay in the Loop

Get the latest updates delivered straight to your inbox