The File Conversion API for Developers
Convert documents, images, and PDFs between dozens of formats. A simple REST API to integrate in minutes and scale to millions of conversions.
# 1. Send your file
curl -X POST \
https://api.convertfilefast.com/v2/convert/docx-to-pdf \
-H "X-API-Key: your_key" \
-F "file=@report.docx" \
-o report.pdf
# Response: converted in <2s
# HTTP 200 OK
# Content-Type: application/pdf
# X-Conversion-Time: 1.24sReal numbers
Trusted by developers around the world
Simple as that
How It Works
Integrate Convert File Fast in 3 simple steps and start converting files today.
Get your API Key
Create your account for free and generate an API key in seconds. No credit card required to start.
Send your File
Make a POST with your file via multipart/form-data. We support documents, images, PDFs and many more formats.
Receive the Result
In less than 2 seconds, receive the converted file directly in the API response. No polling, no callbacks, no complexity.
Conversions
What You Can Convert
60+ conversion types across documents, images, PDFs and data formats. New formats added continuously.
Documents → PDF
DOCX, XLSX, PPTX, CSV, HTML, Markdown, URL and more
Image Conversion
JPG ↔ PNG, HEIC → JPG, SVG → PNG, WebP and more
Images → PDF
JPG, PNG, HEIC, WebP, SVG, BMP, TIFF to PDF
PDF → Other Formats
PDF to JPG, PNG, TXT, DOCX, XLSX, CSV
Data Conversion
JSON ↔ CSV, CSV ↔ XLSX
PDF Operations
Merge, Split, Compress, Rotate, Protect, Unlock
Image Operations
Resize, Compress with quality control
Need a specific format? Contact us and we'll add support quickly.
Advantages
Why Convert File Fast?
Built for developers who need reliable, fast and privacy-respecting file conversion.
API-First
Integrate with any language via standard REST API. Complete documentation with examples in cURL, Python, Node.js and more.
Ultra-Fast Conversion
Processing in under 2 seconds for most files. Infrastructure optimized for high performance.
Guaranteed Privacy
Your files are processed in memory and deleted immediately after conversion. Zero permanent storage.
Auto Scaling
From 50 to millions of conversions per month. Our infrastructure grows automatically with your business demand.
Robust Security
API key authentication, mandatory HTTPS, rate limiting and real-time anomaly monitoring.
High Fidelity
Complete preservation of formatting, fonts, images and layouts. The converted file is identical to the original.
Batch Conversion
Convert multiple files in a single request. Merge PDFs, batch process images and more. Ideal for automations.
Dedicated Support
Technical team available to help with integration. Pro and Scale plans include priority support and guaranteed SLA.
Pricing
Simple and Transparent
Start free and scale as you need.
Free
Perfect for testing the API.
- 10 conversions per month
- Max size: 5MB
- 1 API key
- All formats
- Email support
Pro
For developers and production apps.
- 5,000 conversions per month
- Max size: 50MB
- 5 API keys
- All formats
- Priority support
Scale
For large-scale operations.
- 50,000 conversions per month
- Max size: 200MB
- Unlimited API keys
- Guaranteed SLA
- Dedicated manager
No! The Free plan is completely free and requires no credit card. You get 10 conversions per month automatically when you create your account. We only need payment when you want to upgrade to a paid plan.
Most conversions are completed in under 2 seconds. Larger or more complex files (with many images, for example) may take up to 5 seconds. Our infrastructure is optimized for high performance and low latency.
No. Your files are processed in memory and deleted immediately after conversion. We don't keep any copy of your documents. The privacy and security of your data is our top priority.
We support 60+ conversion types: documents to PDF (DOCX, XLSX, PPTX, CSV, HTML, Markdown), image conversions (JPG, PNG, WebP, HEIC, SVG), PDF to other formats (JPG, PNG, TXT, DOCX), data conversions (JSON, CSV, XLSX), plus PDF operations like merge, split, compress and protect. New formats are added continuously.
Yes! You can merge multiple PDFs, batch convert images, and process multiple files in a single request. This is ideal for automations and high-volume processes.
Yes, credits renew monthly. On the Free plan, it's 10 conversions per month. On paid plans (Pro and Scale) credits renew every month. Unused credits don't accumulate for the next month, but you can also buy one-time credits that don't expire.
We offer 99.9% guaranteed uptime. For Scale plan customers, we offer contractual SLA with account credit if uptime falls below target. We continuously monitor all API endpoints.
It's very simple: just make a POST to our v2 endpoint with your file and the X-API-Key header. Each conversion type has its own endpoint (e.g. /v2/convert/docx-to-pdf). We have complete documentation with examples in cURL, Python, Node.js, Go, PHP and Ruby. Most developers integrate in under 30 minutes.