Convert HTML, Markdown, and URLs to PDF. Built-in invoice & receipt templates.
+All conversion and template endpoints require an API key. Pass it in the Authorization header:
Authorization: Bearer df_free_your_api_key_here+
Get a free API key instantly — no credit card required:
+curl -X POST https://docfast.dev/v1/signup/free \
+ -H "Content-Type: application/json" \
+ -d '{"email": "you@example.com"}'
+ Convert raw HTML (with optional CSS) to a PDF document.
+ +| Field | Type | Description |
|---|---|---|
html required | string | HTML content to convert |
css | string | Additional CSS to inject |
format | string | Page size: A4 (default), Letter, Legal, A3 |
landscape | boolean | Landscape orientation (default: false) |
margin | object | {top, right, bottom, left} in CSS units (default: 20mm each) |
curl -X POST https://docfast.dev/v1/convert/html \
+ -H "Authorization: Bearer YOUR_KEY" \
+ -H "Content-Type: application/json" \
+ -d '{
+ "html": "<h1>Hello World</h1><p>Generated by DocFast.</p>",
+ "css": "h1 { color: navy; }",
+ "format": "A4"
+ }' \
+ -o output.pdf
+
+ 200 OK — Returns the PDF as application/pdf binary stream.
html field
+ 401 Invalid/missing API key
+ 429 Rate limited
+ Convert Markdown to a styled PDF with syntax highlighting for code blocks.
+ +| Field | Type | Description |
|---|---|---|
markdown required | string | Markdown content |
css | string | Additional CSS to inject |
format | string | Page size (default: A4) |
landscape | boolean | Landscape orientation |
margin | object | Custom margins |
curl -X POST https://docfast.dev/v1/convert/markdown \
+ -H "Authorization: Bearer YOUR_KEY" \
+ -H "Content-Type: application/json" \
+ -d '{
+ "markdown": "# Monthly Report\n\n## Summary\n\nRevenue increased by **15%** this quarter.\n\n| Metric | Value |\n|--------|-------|\n| Users | 1,234 |\n| MRR | $5,670 |"
+ }' \
+ -o report.pdf
+
+ 200 OK — Returns application/pdf.
markdown field
+ 401 Invalid/missing API key
+ Navigate to a URL and convert the rendered page to PDF. Supports JavaScript-rendered pages.
+ +| Field | Type | Description |
|---|---|---|
url required | string | URL to convert (must start with http:// or https://) |
waitUntil | string | load (default), domcontentloaded, networkidle0, networkidle2 |
format | string | Page size (default: A4) |
landscape | boolean | Landscape orientation |
margin | object | Custom margins |
curl -X POST https://docfast.dev/v1/convert/url \
+ -H "Authorization: Bearer YOUR_KEY" \
+ -H "Content-Type: application/json" \
+ -d '{
+ "url": "https://example.com",
+ "waitUntil": "networkidle0",
+ "format": "Letter"
+ }' \
+ -o page.pdf
+
+ 200 OK — Returns application/pdf.
List all available document templates with their field definitions.
+ +curl https://docfast.dev/v1/templates \ + -H "Authorization: Bearer YOUR_KEY"+ +
{
+ "templates": [
+ {
+ "id": "invoice",
+ "name": "Invoice",
+ "description": "Professional invoice with line items, taxes, and payment details",
+ "fields": [
+ {"name": "invoiceNumber", "type": "string", "required": true},
+ {"name": "date", "type": "string", "required": true},
+ {"name": "from", "type": "object", "required": true, "description": "Sender: {name, address?, email?, phone?, vatId?}"},
+ {"name": "to", "type": "object", "required": true, "description": "Recipient: {name, address?, email?, vatId?}"},
+ {"name": "items", "type": "array", "required": true, "description": "Line items: [{description, quantity, unitPrice, taxRate?}]"},
+ {"name": "currency", "type": "string", "required": false},
+ {"name": "notes", "type": "string", "required": false},
+ {"name": "paymentDetails", "type": "string", "required": false}
+ ]
+ },
+ {
+ "id": "receipt",
+ "name": "Receipt",
+ "description": "Simple receipt for payments received",
+ "fields": [ ... ]
+ }
+ ]
+}
+ Render a template with your data and get a PDF. No HTML needed — just pass structured data.
+ +| Param | Description |
|---|---|
:id | Template ID (invoice or receipt) |
| Field | Type | Description |
|---|---|---|
data required | object | Template data (see field definitions from /v1/templates) |
curl -X POST https://docfast.dev/v1/templates/invoice/render \
+ -H "Authorization: Bearer YOUR_KEY" \
+ -H "Content-Type: application/json" \
+ -d '{
+ "data": {
+ "invoiceNumber": "INV-2026-001",
+ "date": "2026-02-14",
+ "dueDate": "2026-03-14",
+ "from": {
+ "name": "Acme Corp",
+ "address": "123 Main St, Vienna",
+ "email": "billing@acme.com",
+ "vatId": "ATU12345678"
+ },
+ "to": {
+ "name": "Client Inc",
+ "address": "456 Oak Ave, Berlin",
+ "email": "accounts@client.com"
+ },
+ "items": [
+ {"description": "Web Development", "quantity": 40, "unitPrice": 95, "taxRate": 20},
+ {"description": "Hosting (monthly)", "quantity": 1, "unitPrice": 29}
+ ],
+ "currency": "€",
+ "notes": "Payment due within 30 days.",
+ "paymentDetails": "IBAN: AT12 3456 7890 1234 5678"
+ }
+ }' \
+ -o invoice.pdf
+
+ 200 OK — Returns application/pdf.
data field
+ 404 Template not found
+ 401 Invalid/missing API key
+ Get a free API key instantly. No authentication required.
+ +| Field | Type | Description |
|---|---|---|
email required | string | Your email address |
curl -X POST https://docfast.dev/v1/signup/free \
+ -H "Content-Type: application/json" \
+ -d '{"email": "dev@example.com"}'
+
+ {
+ "message": "Welcome to DocFast! 🚀",
+ "apiKey": "df_free_abc123...",
+ "tier": "free",
+ "limit": "100 PDFs/month",
+ "docs": "https://docfast.dev/#endpoints"
+}
+ All errors return JSON with an error field:
{
+ "error": "Missing 'html' field"
+}
+
+ | Code | Meaning |
|---|---|
200 | Success — PDF returned as binary stream |
400 | Bad request — missing or invalid parameters |
401 | Unauthorized — missing or invalid API key |
404 | Not found — invalid endpoint or template ID |
429 | Rate limited — too many requests (100/min) |
500 | Server error — PDF generation failed |
# ❌ Missing Authorization header +curl -X POST https://docfast.dev/v1/convert/html \ + -d '{"html": "test"}' +# → {"error": "Missing API key. Use: Authorization: Bearer <key>"} + +# ❌ Wrong Content-Type +curl -X POST https://docfast.dev/v1/convert/html \ + -H "Authorization: Bearer YOUR_KEY" \ + -d '{"html": "test"}' +# → Make sure to include -H "Content-Type: application/json" + +# ✅ Correct request +curl -X POST https://docfast.dev/v1/convert/html \ + -H "Authorization: Bearer YOUR_KEY" \ + -H "Content-Type: application/json" \ + -d '{"html": "<h1>Hello</h1>"}' \ + -o output.pdf+
One API call. Beautiful PDFs. Built-in invoice templates. No headless browser setup, no dependencies, no hassle.
Here's your API key. Save it now — it won't be shown again.
100 free PDFs/month • All endpoints • View docs →
+100 free PDFs/month • All endpoints • View docs →
Save this key! It won't be shown again.
10,000 PDFs/month • All endpoints • Priority support
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