ForHosting KIT · Data & Files

JSON to CSV

The moment your JSON has a nested object or an array inside a field, "just convert it to CSV" stops being trivial — a spreadsheet has no native concept of a document within a cell. This endpoint flattens nested JSON into consistent, well-named columns, so the file that comes out opens cleanly in any spreadsheet tool instead of showing a wall of unreadable bracket-and-brace text.

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The mismatch between documents and rows

JSON is built to nest: an order can contain a customer object, which contains an address object, which contains an array of previous orders, each with its own line items. CSV has no way to express that — it is fundamentally a grid of rows and columns, one flat record per line. Anyone who has tried to hand-roll this conversion knows the usual failure mode: a naive tool just calls JSON.stringify on the nested part and dumps a blob of escaped curly braces into a single cell, which technically "works" but produces a spreadsheet nobody can filter, sort or open in a reporting tool.

How the flattening actually behaves

Send your JSON array or document to POST /data/json-to-csv and nested objects are unrolled into dot-notated columns — an address.city field sits next to address.country rather than being buried inside a single blob — while arrays of scalar values are joined predictably and arrays of objects are expanded according to a strategy suited to the shape of your data, so line items in an order become their own set of readable columns instead of an opaque string. Column headers are derived directly from the structure of your JSON, keeping the mapping between source field and output column obvious to anyone opening the file later.

Why this still matters when everything is an API

It would be easy to assume CSV is a legacy concern now that most systems exchange JSON natively, but the spreadsheet remains the interface non-technical stakeholders actually trust. Finance teams reconcile in spreadsheets, operations teams build pivot tables from them, and plenty of business tools still only accept CSV as an import format. Converting API output into CSV is less about technology and more about meeting people where they already work.

Handling irregular records without breaking the grid

Real JSON collections are rarely perfectly uniform — one order has a discount field and the next does not, one customer record has three phone numbers and another has none. The conversion reconciles differing shapes across records into a single consistent header row, filling absent fields rather than shifting columns out of alignment, which is the single most common way hand-written converters silently corrupt a spreadsheet.

Fitting into automated reporting

Because the task runs asynchronously, it works well at the end of a reporting pipeline: pull records from your application's API, convert the resulting JSON to CSV here, and deliver the file straight to an analyst's inbox or a shared drive without a script babysitting the transformation. You receive a task_id right away and the CSV lands by webhook, ready to attach or forward.

What you can do with it

Weekly finance export

Convert order or transaction JSON pulled from your API into a CSV that finance can open directly in a spreadsheet for reconciliation.

CRM data handoff

Turn nested customer records, including arrays of contacts or interactions, into a flat CSV a sales team can import into their existing tools.

Analytics tool import

Flatten event or log JSON into CSV for business intelligence tools that only accept tabular import files.

Client deliverable

Package API results as a clean CSV attachment for a non-technical client instead of sending raw JSON they cannot open.

FAQ

How does this JSON to CSV API handle nested objects?

Nested objects are flattened into dot-notated columns, such as address.city, so every value gets its own readable column instead of being embedded as raw JSON text.

What happens to arrays inside my JSON?

Arrays of simple values are joined predictably within a column, and arrays of objects, like order line items, are expanded into their own set of columns rather than collapsed into an unreadable string.

Can it handle JSON records with inconsistent fields?

Yes, the conversion reconciles differing record shapes into one consistent header row, filling missing fields so columns never shift out of alignment.

Is there a free trial for the JSON to CSV endpoint?

The tool above runs free in your browser. The API is paid — each call draws from your prepaid ForHosting KIT balance: top up from $10.00 (it never expires), pay each request's published price, and a call with no balance returns HTTP 402. No subscription, no tokens, and a failed task is never charged.

Can I convert large JSON arrays with thousands of records?

Yes, submit the array as an async request and it processes as a single task; for very large or recurring exports, batching by date range or ID is a common pattern.

What if the JSON to CSV conversion fails?

It automatically retries up to three times; if it still fails, you get a clear error and are not charged for the attempt.

How do I retrieve the generated CSV file?

Via a signed webhook, recommended for pipelines, or a signed link valid for 24 hours if you want to download it manually.

How much does converting JSON to CSV cost?

$0.002 per request, billed only when the conversion completes successfully.

For developers — API access

Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.

API endpoint

POSThttps://api.kit.forhosting.com/data/json-to-csv

Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, and soon from our app, email and Telegram.

Call it from your stack

curl -X POST https://api.kit.forhosting.com/data/json-to-csv \
  -H "Authorization: Bearer $KIT_KEY" \
  -H "Content-Type: application/json" \
  -d &#39;{"text":"…"}'

const res = await fetch("https://api.kit.forhosting.com/data/json-to-csv", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.KIT_KEY}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    "text": "…"
  })
});
const { task_id } = await res.json();

import os, requests

res = requests.post(
    "https://api.kit.forhosting.com/data/json-to-csv",
    headers={"Authorization": f"Bearer {os.environ[&#39;KIT_KEY']}"},
    json={
    "text": "…"
},
)
task_id = res.json()["task_id"]

<?php
$res = file_get_contents("https://api.kit.forhosting.com/data/json-to-csv", false, stream_context_create([
  "http" => [
    "method"  => "POST",
    "header"  => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
    "content" => &#39;{"text":"…"}',
  ],
]));
$task = json_decode($res, true);

body := bytes.NewBufferString(`{"text":"…"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/data/json-to-csv", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)

Example request

{
  "text": "…"
}

Example response

{
  "task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
  "type": "data.json_to_csv",
  "status": "queued",
  "_links": {
    "result": "/tasks/tsk_…/result"
  }
}

The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.

Pricing

Per request$0.002

Published price — no tokens, no invented credits. A failed task is never charged.

Limits

max_mb 25

Errors

HTTP	Code	Meaning
`401`	`unauthorized`	Missing or invalid API key.
`402`	`insufficient_balance`	Your balance doesn't cover the task price.
`404`	`unknown_type`	That task type doesn't exist.
`429`	`rate_limited`	Too many requests. Use the webhook instead of polling.

Read the full KIT documentation →

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