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Frequently Asked Questions

General Questions

What file formats are supported for Arcface API?

ArcFont supports common image formats:

  • PNG (recommended)
  • JPEG/JPG
  • Maximum file size: 5MB

Getting Started

Do you offer a free tier?

No, but we offer free credits for new user.

API Usage

What's the difference between the three endpoints?

  • Embedding Generation (/embedding): Returns a 1024-dimensional vector representing font characteristics
  • Font Comparison (/font_comparison): Compares two fonts and returns similarity metrics
  • Font Search (/font_search): Finds similar fonts in our database

How many requests can I make?

Rate limits are generous and based on trafic. Typical limits:

  • 80 requests/minute for embedding and comparison
  • 50 requests/minute for font search

What's included in font search results?

Font search returns up to 10 similar fonts with:

  • Font name and family
  • Variant (Bold, Italic, etc.)
  • Category (Sans-serif, Serif, etc.)
  • Similarity distance score
  • Source URL when available

Technical Questions

What do the embedding vectors represent?

The 1024-dimensional vectors capture visual font characteristics like:

  • Character spacing and proportions
  • Serif vs sans-serif features
  • Overall geometric properties

How do I interpret similarity scores?

Cosine Similarity (-1 to 1):
  • 1-0.8 = Probably identical fonts
  • 0.6-0.8 = Very similar fonts
  • Below 0.6 = Different fonts

Can I compare fonts without using the comparison endpoint?

Yes! Generate embeddings for both fonts and calculate cosine similarity yourself:

Image Quality

What makes a good font image?

Best practices:

  • Square format images
  • Text height 7-39% of image height
  • High contrast (dark text on light background or vice versa)
  • Clear, unrotated text
  • Single font family per image

Why am I getting poor results?

Common issues:

  • Text too small: Increase text size or use smaller image
  • Multiple fonts: Use only one font family per image
  • Poor contrast: Ensure text stands out from background

Can I use photos of text from books or signs?

Yes it can handle photos.

How is usage calculated?

Each API call is counted individually:
  • Successful calls (200 OK) are billed
  • Failed calls (4xx, 5xx errors) are typically not billed

Can I get volume discounts?

Yes! Contact support@caoslabs.com to discuss enterprise pricing for high-volume usage.

What payment methods do you accept?

Any credit or debit card, we use stripe to handle payents.

Integration & Development

Do you have SDKs for different languages?

Currently, we provide comprehensive code examples for:

  • Python
  • JavaScript/Node.js
  • cURL
See our Code Examples section for ready-to-use implementations.

Can I use this in a web application?

Yes! ArcFont works great in web applications. You can:

  • Call the API from your backend
  • Use it in serverless functions
  • Integrate with file upload forms

Security

How should I store my API tokens?

Best practices:

  • Use environment variables or .env file
  • Never commit tokens to version control
  • Use different tokens for different environments
  • Rotate tokens regularly

Is my data secure?

Yes:

  • All API calls use HTTPS encryption
  • We don't retain your uploaded images
  • Tokens can be revoked at any time

Troubleshooting

I'm getting "Unauthorized" errors

Check:

  • API token is correct
  • Token is included in Authorization header: Bearer YOUR_TOKEN
  • Token hasn't been revoked
  • You're using the correct API endpoint

My requests are timing out

Solutions:

  • Reduce image file size
  • Check your internet connection
  • Implement retry logic with exponential backoff
  • Use smaller, optimized images

The API returns 5xx errors

These are temporary server issues:

  • Implement retry logic
  • Wait a few seconds between retries
  • Contact support if issues persist

Still Need Help?

Can't find the answer you're looking for?

We typically respond to support requests within 24 hours.