We often get asked: “Why not just send everything to ChatGPT API?”

While GPT-4o is powerful, using a general-purpose LLM for high-volume document processing has hidden costs.

1. Cost per Document

  • GPT-4o: You pay for input tokens (entire PDF text) + output tokens. For a dense financial report, this adds up quickly.
  • Dedicated API: ParserData offers predictable pricing per document, which is typically 40-60% cheaper at scale for specialized tasks like Invoice or Receipt parsing.

2. Latency

  • General LLMs can take 10-30 seconds to “reason” through a document.
  • Specialized models are optimized for extraction speed (<5 seconds).

3. Hallucinations

  • General models might “invent” a Total amount if the scan is blurry.
  • Dedicated parsers are constrained to extract only what is visibly present.

Verdict: Use GPT-4o for creative tasks (summarizing a letter). Use a specialized engine like ParserData for structured data extraction where accuracy and speed are critical.

What is your experience with API costs for document processing?