# Stock Split Calculator API

> For the complete documentation index, see [llms.txt](/llms.txt).

Post-split shares, price, cost basis, and fractional-share handling for forward and reverse stock splits.

Use this endpoint to add the tool to your app, site, workflow, or agent without rebuilding formulas, validation, examples, and docs.

- Slug: `stock-split-calculator`
- Category: `finance`
- Version: `2026-04-22`
- Credits per successful call: 2
- Starts on: free
- Max payload: 65536 bytes
- Privacy mode: `hash_only`
- Available on: free, starter, pro, business, scale
- Browser tool: https://miniwebtool.com/stock-split-calculator/

## Endpoint

`POST https://api.miniwebtool.com/v1/tools/stock-split-calculator/run`

## Request body

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `current_shares` | `float` | no |  |
| `current_price` | `float` | no |  |
| `split_new` | `float` | no | New shares per split_old shares (e.g. 2 in 2-for-1) |
| `split_old` | `float` | no | Old shares in the ratio (e.g. 1 in 2-for-1) |
| `cost_basis_per_share` | `float | None` | no |  |
| `fractional_policy` | `str` | no | fractional | cash | round_down Choices: fractional, cash, round_down |

## Example request

```json
{
  "current_shares": 100,
  "current_price": 150,
  "split_new": 2,
  "split_old": 1
}
```

## cURL

```bash
curl -X POST https://api.miniwebtool.com/v1/tools/stock-split-calculator/run \
  -H 'Authorization: Bearer mwt_live_YOUR_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"current_shares":100,"current_price":150,"split_new":2,"split_old":1}'
```

## Response envelope

```json
{
  "request_id": "01K...",
  "tool": "stock-split-calculator",
  "tool_version": "2026-04-22",
  "credits_used": 2,
  "result": {}
}
```

## Errors

Errors are RFC 7807 `application/problem+json`. Branch on `code`, not `title`.

## MCP

Agents can discover and call this tool through `https://api.miniwebtool.com/mcp` or `https://api.miniwebtool.com/v1/mcp` using MCP `tools/list` and `tools/call`.

## Frequently asked

### What does the Stock Split Calculator API do?

Post-split shares, price, cost basis, and fractional-share handling for forward and reverse stock splits. Use it to add this utility without rebuilding formulas, validation, examples, and documentation.

### How much does one call cost?

2 credits per successful call. Failed calls do not bill.

### What parameters are required?

Required fields: (none). Full schema at `https://api.miniwebtool.com/v1/openapi.json`.

### Is this deterministic?

Yes. Same input, same output. Tool version: 2026-04-22.