# Savings growth calculator (GET /calculators/savings-growth)

Source: DepositScout Data API docs — https://depositscout.com/developers/docs/calculators.savings-growth

A starting balance and monthly deposits growing at a fixed rate: end balance, total paid in, interest, and the balance at the end of each year.

---

Up to 50 years.

- **Cost:** 1 DS Credit per request
- **Scope:** `any key`
- **Same data as:** the DepositScout website

## Request

`GET https://depositscout.com/api/developer/v1/calculators/savings-growth`

| Parameter | In | Type | Example | Description |
| --- | --- | --- | --- | --- |
| rate* | query | number | 4.5 | AER, e.g. 4.5. |
| months* | query | integer | 60 | How long, 1 to 600 months. |
| amount | query | number | 10000 | Starting balance in pounds. |
| monthly | query | number | 200 | Paid in at the end of every month, in pounds. |
| compounding | query | enum | — | annual (rate is an AER, the default) or monthly (rate ÷ 12 each month).`annual` `monthly` |

## Example

**curl**

```bash
curl "https://depositscout.com/api/developer/v1/calculators/savings-growth?rate=4.5&months=60&amount=10000&monthly=200" \
  -H "Authorization: Bearer $DS_API_KEY"
```

**Node**

```javascript
const res = await fetch("https://depositscout.com/api/developer/v1/calculators/savings-growth?rate=4.5&months=60&amount=10000&monthly=200", {
  headers: { Authorization: `Bearer ${process.env.DS_API_KEY}` },
});
const { data, meta } = await res.json();
console.log(meta.creditsCharged, data);
```

**Python**

```python
import os, requests

res = requests.get(
    "https://depositscout.com/api/developer/v1/calculators/savings-growth?rate=4.5&months=60&amount=10000&monthly=200",
    headers={"Authorization": f"Bearer {os.environ['DS_API_KEY']}"},
)
body = res.json()
print(body["meta"]["creditsCharged"], body["data"])
```

**MCP (tool call)**

```mcptoolcall
curl https://depositscout.com/api/mcp \
  -H "Authorization: Bearer $DS_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"calculators_savings_growth","arguments":{"rate":4.5,"months":60,"amount":10000,"monthly":200}}}'
```

## Response

`data` is a single object. Every 2xx also sets `X-DS-Request-Id`, `X-DS-Credits-Charged`, `X-DS-Credits-Balance`, the `X-RateLimit-*` trio and an `ETag`.

```json
{
  "data": {
    "…": "the item"
  },
  "meta": {
    "requestId": "req_7f3a9c2d1b4e5a6f7c8d",
    "generatedAt": "2026-09-21T09:00:00.000Z",
    "creditsCharged": 1,
    "creditsBalance": 199,
    "attribution": "Rates powered by DepositScout — depositscout.com"
  }
}
```

## Errors

What this endpoint can return instead of data. Every error has the same shape: `error` (a stable code to branch on), `message` (what to do next), `requestId` and a `docs` link, plus the extra fields shown. None of them is charged.

401 `missing_api_key` — No Authorization header, or it isn't a Bearer token.

```json
{
  "error": "missing_api_key",
  "message": "Send your key as 'Authorization: Bearer ds_live_…'. Create one at https://depositscout.com/developer.",
  "requestId": "req_7f3a9c2d1b4e5a6f7c8d",
  "docs": "https://depositscout.com/developers/docs#missing_api_key"
}
```

402 `insufficient_credits` — Balance is lower than the call's cost. A list whose page you can't fully afford is cut to the rows your balance covers instead (meta.limit and X-DS-Limit-Reduced say so), so this only happens below one row's price. Body has required, balance and topUp.

```json
{
  "error": "insufficient_credits",
  "message": "Not enough DS Credits for this request. Top up at https://depositscout.com/developer/credits.",
  "requestId": "req_7f3a9c2d1b4e5a6f7c8d",
  "docs": "https://depositscout.com/developers/docs#insufficient_credits",
  "required": 1,
  "balance": 0,
  "topUp": "https://depositscout.com/developer/credits"
}
```

429 `rate_limited` — Burst or daily limit hit. Retry-After tells you when.

```json
{
  "error": "rate_limited",
  "message": "Too many requests. Retry after 12s.",
  "requestId": "req_7f3a9c2d1b4e5a6f7c8d",
  "docs": "https://depositscout.com/developers/docs#rate_limited",
  "retryAfter": 12
}
```

Every code is listed in the [shared error contract](https://depositscout.com/developers/docs#errors). Back to [all endpoints](https://depositscout.com/developers/docs#endpoints).