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OnlyDocs API: The Complete Developer Guide for PDF Automation (2025)

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OnlyDocs Team
OnlyDocs Team

OnlyDocs API: The Complete Developer Guide for PDF Automation (2025)

Need to programmatically manipulate PDFs in your application? Tired of Adobe's $25k-$55k/year API pricing? OnlyDocs API gives you enterprise-grade PDF processing at $29.99/month with unlimited requests.

This guide covers everything you need to integrate OnlyDocs API into your application.

Why OnlyDocs API?

The Problem with Traditional PDF APIs

Adobe PDF Services API: $25,000-$55,000/year PDFtron: Enterprise pricing (typically $10k-$50k+) ILovePDF API: $6/1000 requests PDF.co: $99/month for 5,000 API calls

The OnlyDocs Solution

Business Tier: $29.99/month

  • Unlimited API requests
  • 30+ endpoints
  • 100 requests/minute rate limit
  • No per-request fees
  • 94-99% cost savings

ROI Example:

  • 1 million API calls/month
  • OnlyDocs: $29.99
  • ILovePDF: $6,000
  • Savings: $5,970/month ($71,640/year)

Getting Started

1. Sign Up for Business Tier

# Visit onlydocs.net
# Click "Pricing" → "Business" → "Upgrade"
# Complete payment ($29.99/month)

2. Generate API Key

# Navigate to Settings → API Keys
# Click "Generate New Key"
# Copy your key: od_xxxxxxxxxxxxxxxxxx
# Store securely (never commit to git!)

3. Test Your First Request

const response = await fetch('https://api.onlydocs.net/v1/editor/merge', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer od_your_api_key',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    pdfs: [pdfBase64_1, pdfBase64_2]
  })
});

const result = await response.json();
console.log(result.data.pdfBase64); // Merged PDF

Core API Categories

1. PDF Editing (/api/v1/editor/*)

Merge PDFs

POST /editor/merge
Combine multiple PDFs into one

Split PDFs

POST /editor/split
Split PDF by page ranges or extract specific pages

Rotate Pages

POST /editor/rotate
Rotate pages 90°, 180°, or 270°

Reorder Pages

POST /editor/reorder
Rearrange page order

Delete Pages

POST /editor/delete-pages
Remove specific pages

Add Blank Pages

POST /editor/add-blank-pages
Insert blank pages at specified positions

Compress PDF

POST /editor/compress
Reduce file size while maintaining quality

Extract Text

POST /editor/extract-text
Pull text content from PDF

Extract Images

POST /editor/extract-images
Get all images from PDF

Extract Tables

POST /editor/extract-tables
Convert PDF tables to JSON/CSV

Page Info

POST /editor/page-info
Get page count, dimensions, metadata

Metadata

POST /editor/metadata
Read/write PDF metadata (title, author, etc.)

Flatten Forms

POST /editor/flatten
Convert fillable forms to static content

Fill Forms

POST /editor/fill-form
Programmatically fill PDF form fields

2. Conversions (/api/v1/convert/*)

HTML to PDF

POST /convert/html-to-pdf
Convert HTML string or URL to PDF

URL to PDF

POST /convert/url-to-pdf
Capture web pages as PDFs

Images to PDF

POST /editor/images-to-pdf
Combine JPG/PNG images into PDF

PDF to Images

POST /convert/pdf-to-image
Export each page as PNG/JPG

PDF to DOCX

POST /convert/pdf-to-docx
Convert to Microsoft Word format

PDF to HTML

POST /convert/pdf-to-html
Export as HTML document

PDF to Text

POST /convert/pdf-to-txt
Extract plain text

PDF to Excel

POST /convert/pdf-to-xlsx
Convert tables to spreadsheet

OCR (Optical Character Recognition)

POST /convert/ocr
Extract text from scanned documents/images

3. Document Operations (/api/v1/editor/*)

Rotate Pages

POST /editor/rotate
Rotate pages clockwise/counterclockwise

Delete Pages

POST /editor/delete-pages
Remove specified pages from PDF

Reorder Pages

POST /editor/reorder
Change page sequence

4. Async Jobs (/api/v1/async/*)

For large files or batch operations:

POST /async/html-to-pdf    # Start async job
GET /async/jobs/{jobId}     # Check status
GET /async/jobs             # List all jobs

Real-World Use Cases

Use Case 1: Invoice Generation SaaS

// Generate 1000 invoices from templates
async function generateInvoices(customers) {
  const invoices = await Promise.all(
    customers.map(customer =>
      fetch('https://api.onlydocs.net/v1/convert/html-to-pdf', {
        method: 'POST',
        headers: {
          'Authorization': `Bearer ${process.env.ONLYDOCS_API_KEY}`,
          'Content-Type': 'application/json'
        },
        body: JSON.stringify({
          html: generateInvoiceHTML(customer),
          options: {
            format: 'A4',
            margin: { top: '20mm', bottom: '20mm' }
          }
        })
      }).then(r => r.json())
    )
  );

  return invoices; // Array of PDF base64 strings
}

Cost with OnlyDocs: $29.99/month Cost with ILovePDF: $6/1000 = $6.00 Monthly at 100k invoices: OnlyDocs $29.99 vs ILovePDF $600

Use Case 2: Document Processing Pipeline

// OCR → Extract Tables → Convert to Excel
async function processDocument(pdfBase64) {
  // Step 1: OCR scanned document
  const ocrResult = await fetch('https://api.onlydocs.net/v1/convert/ocr', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({ pdfBase64, language: 'eng' })
  }).then(r => r.json());

  // Step 2: Extract tables
  const tables = await fetch('https://api.onlydocs.net/v1/editor/extract-tables', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({ pdfBase64: ocrResult.data.pdfBase64 })
  }).then(r => r.json());

  // Step 3: Convert to Excel
  const xlsx = await fetch('https://api.onlydocs.net/v1/convert/pdf-to-xlsx', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({ pdfBase64: ocrResult.data.pdfBase64 })
  }).then(r => r.json());

  return xlsx.data;
}

Use Case 3: Compliance Document Generator

// Merge contracts and compress for distribution
async function generateCompliancePackage(documents) {
  // Merge all documents
  const merged = await fetch('https://api.onlydocs.net/v1/editor/merge', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({ pdfs: documents })
  }).then(r => r.json());

  // Compress for easy distribution
  const compressed = await fetch('https://api.onlydocs.net/v1/editor/compress', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      pdfBase64: merged.data.pdfBase64,
      compressionLevel: 'high'
    })
  }).then(r => r.json());

  return compressed.data.pdfBase64;
}

API Best Practices

1. Error Handling

async function callAPI(endpoint, body) {
  try {
    const response = await fetch(`https://api.onlydocs.net/v1${endpoint}`, {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${API_KEY}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify(body)
    });

    if (!response.ok) {
      const error = await response.json();
      throw new Error(`API Error: ${error.message}`);
    }

    return await response.json();
  } catch (err) {
    console.error('OnlyDocs API failed:', err);
    throw err;
  }
}

2. Rate Limiting

// Batch requests with rate limiting (100 req/min)
const rateLimit = require('p-ratelimit');

const limit = rateLimit({
  interval: 60 * 1000, // 60 seconds
  rate: 100,           // 100 requests
  concurrency: 10      // 10 concurrent requests
});

async function processBatch(items) {
  return await Promise.all(
    items.map(item =>
      limit(() => callAPI('/editor/merge', item))
    )
  );
}

3. Large Files (Use Async)

// For PDFs > 10MB, use async endpoints
async function processLargeFile(pdfBase64) {
  // Start job
  const job = await fetch('https://api.onlydocs.net/v1/async/html-to-pdf', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({ html: largeHTML })
  }).then(r => r.json());

  // Poll for completion
  let status = 'processing';
  while (status === 'processing') {
    await new Promise(resolve => setTimeout(resolve, 2000)); // Wait 2s

    const result = await fetch(`https://api.onlydocs.net/v1/async/jobs/${job.data.jobId}`, {
      headers: { 'Authorization': `Bearer ${API_KEY}` }
    }).then(r => r.json());

    status = result.data.status;

    if (status === 'completed') {
      return result.data.result;
    }
  }
}

Security Best Practices

1. Store API Keys Securely

# Environment variables (never commit!)
ONLYDOCS_API_KEY=od_xxxxxxxxxxxx

# .gitignore
.env
.env.local

// Use dotenv or similar
require('dotenv').config();
const API_KEY = process.env.ONLYDOCS_API_KEY;

2. Use Server-Side Only

// ❌ BAD - Exposes API key to client
fetch('https://api.onlydocs.net/v1/editor/merge', {
  headers: { 'Authorization': `Bearer od_xxxxx` } // Visible in browser!
});

// ✅ GOOD - Keep on backend
// Backend API route
app.post('/api/merge-pdfs', async (req, res) => {
  const result = await fetch('https://api.onlydocs.net/v1/editor/merge', {
    headers: { 'Authorization': `Bearer ${process.env.ONLYDOCS_API_KEY}` }
  });
  res.json(result);
});

3. Validate Input

function validatePDFBase64(str) {
  // Check if valid base64
  if (!/^[A-Za-z0-9+/=]+$/.test(str)) {
    throw new Error('Invalid PDF base64');
  }

  // Check reasonable size (e.g., < 50MB)
  if (str.length > 50 * 1024 * 1024) {
    throw new Error('PDF too large');
  }

  return true;
}

Performance Optimization

1. Compress PDFs Before Upload

// Compress before sending if possible
const compressed = await fetch('https://api.onlydocs.net/v1/editor/compress', {
  method: 'POST',
  headers: {
    'Authorization': `Bearer ${API_KEY}`,
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    pdfBase64: largePDF,
    compressionLevel: 'medium'
  })
}).then(r => r.json());

2. Cache Results

const NodeCache = require('node-cache');
const cache = new NodeCache({ stdTTL: 3600 }); // 1 hour

async function getCachedMerge(pdfArray) {
  const cacheKey = hashPDFs(pdfArray);
  const cached = cache.get(cacheKey);

  if (cached) return cached;

  const result = await callAPI('/editor/merge', { pdfs: pdfArray });
  cache.set(cacheKey, result);

  return result;
}

Pricing Comparison

Provider Pricing 1M requests/mo
OnlyDocs $29.99/mo unlimited $29.99
Adobe PDF Services $0.05-0.10/call $50,000-$100,000
PDFtron Enterprise $10,000-$50,000+
ILovePDF API $6/1000 calls $6,000
PDF.co $99/mo (5k calls) $19,800

Support & Resources

Getting Started Today

  1. Upgrade to Business: Visit onlydocs.net/pricing
  2. Generate API Key: Dashboard → Settings → API Keys
  3. Read Full Docs: api.onlydocs.net/docs
  4. Build Your Integration: Start with the examples above
  5. Deploy: No rate limits, no surprises

The Bottom Line

OnlyDocs API gives you enterprise-grade PDF processing at consumer pricing. Whether you're generating 100 or 1,000,000 PDFs per month, you pay the same $29.99.

No per-request fees. No overage charges. No enterprise sales calls.

Ready to save 94-99% on your PDF API costs? Upgrade to Business tier today.

Keywords: PDF API, document processing API, PDF automation, Adobe PDF Services alternative, PDFtron alternative, REST API PDF, developer tools, OnlyDocs API