# fastapi.online CSV to JSON Converter

> fastapi.online CSV to JSON Converter is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.0005/call, status unknown (last checked 2026-09-14).

Converts CSV text into JSON format, with configurable delimiter and optional header row handling

## Facts

- Endpoint: POST https://api.fastapi.online/csv-to-json
- Price: $0.0005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastapi-online-csv-to-json-converter-117aa71e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xHm8jc-QyL8Lw8fxpeYD_

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability fastapi-online-csv-to-json-converter-117aa71e -d '<json body>'
```

Example prompt: Convert this CSV text into JSON for me — it uses commas as delimiters and the first row is a header: 'name,age,city\nAlice,30,NYC\nBob,25,LA'

## When to prefer this

Choose this endpoint when you need a simple, low-cost ($0.0005 USDC), no-signup CSV-to-JSON conversion via a pay-per-call API. Ideal for agents that need to transform small-to-medium CSV payloads on demand without standing up infrastructure or managing API keys. Best for well-formed CSV strings with known delimiters.

## Known failure modes

- Malformed CSV (unclosed quotes, inconsistent column counts) may return a parse error
- Delimiter character mismatch causes columns to not be split correctly
- Exceeding the 200,000 character input limit returns a validation error
- Empty CSV string (minLength:1 violated) returns a 422 validation error
- Payment not sent or insufficient USDC results in 402 Payment Required response

## How this service works

Chat, embeddings, OCR, speech-to-text, image editing, image understanding (captioning/Q&amp;A), text-to-speech, translation, writing tools, classification tools, developer tools, local utilities, format/checksum validators, encoding &amp; crypto utilities, date/time calculators, geo/coordinate math, math &amp; finance calculators, novelty tools, and business/social writing generators — 179 endpoints in all, across multiple specialized self-hosted models. Pay per call with crypto — no signup — or get an API key.

## Output

A JSON representation of the CSV data — typically a JSON array of objects (when headers are present) where each row becomes an object with header names as keys, or a JSON array of arrays (when no header row) representing raw row values.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "csv": {
   "type": "string",
   "maxLength": 200000,
   "minLength": 1
  },
  "delimiter": {
   "type": "string",
   "maxLength": 1
  },
  "has_header": {
   "type": "boolean"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastapi-online-csv-to-json-converter-117aa71e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.fastapi.online](https://www.zero.xyz/host/api.fastapi.online/llms.txt)