# Stochastic RSI

`D07-F03-A03` · Technical Indicators → Momentum · archetype `series-transform` · difficulty 3/5 · verification **verified**

Full page: https://docs.thefintechbuilder.com/technical-indicators/momentum/stochastic-rsi/
Agent skill: `npx skills add IslamBaraka90/Fintech-Algorithms-Library` — https://docs.thefintechbuilder.com/guides/agent-skill/

## Install and import

```bash
npm install fintech-algorithms
```

```ts
import { stochasticRsi } from "fintech-algorithms/technical-indicators/momentum/stochastic-rsi";
```

## Signature

```ts
stochasticRsi(close, rp, sp, sk, sd)
```

The stochastic formula applied to RSI rather than to price — a second-order indicator that measures where RSI sits within its own recent range, and therefore moves far faster than either input.

## Parameters

| Name | Type | Required | Notes |
| --- | --- | --- | --- |
| `close` | `number[]` | yes | Per-bar closing prices, chronological. |
| `rp` | `number` | yes | RSI period computed first. · min: 1, integer: true |
| `sp` | `number` | yes | Stochastic lookback applied over the RSI series. · min: 1, integer: true |
| `sk` | `number` | yes | Smoothing applied to raw %K. · min: 1, integer: true |
| `sd` | `number` | yes | Smoothing applied to %K to produce %D. · min: 1, integer: true |

## Returns

`Record<string, (number | null)[]>` · length same-as-input

Parallel series: `rsi`, `raw_k`, `k` and `d`.

## Warm-up

The first `rp + sp − 1, plus each smoothing stage` positions are `null`. Warm-ups accumulate across both stages, so this is defined much later than plain RSI.

## Errors

- When any period is < 1 or is not an integer — throws RangeError

## Complexity

Time `O(n × sp)`, space `O(n)`.

## Worked example

Captured by running this function on the input its own test provides. Real output of real code — but not asserted against a published figure.

### Input

`close`:

```json
[100, 100.999214, 102.324548, 103.755998, 105.030823, 105.911843]
```

Showing 6 of 120 elements.

### Call

```ts
stochasticRsi(close, rp, sp, sk, sd)
```

### Returns

object with 4 fields: rsi, raw_k, k, d

```json
{
  "rsi": [null, null, null, null, null, null],
  "raw_k": [null, null, null, null, null, null],
  "k": [null, null, null, null, null, null],
  "d": [null, null, null, null, null, null]
}
```

## Other exports

`rsi`, `stochastic`, `williamsR`, `cci`, `ultimateOscillator`, `tsi`, `connorsRsi`. Every module additionally exports `run` as an alias of its primary
function, and a `meta` object carrying its catalog id, domain, family, shape and article URL.

## Verification and provenance

Tier: **verified** (via scenario-fixture).

The worked example below is the figure published in this algorithm's article, replayed and asserted by the test suite on every build. The arithmetic cannot drift without the build failing.

Both tiers guarantee the signature. Full explanation: https://docs.thefintechbuilder.com/guides/verification/

Generated from the docs.json payload shipped inside fintech-algorithms@0.13.1.
The signature and parameter list are checked against the compiled implementation at build time,
so a description that contradicts the code fails the build rather than reaching this file.

## Links

- Article (how it works, step by step): https://thefintechbuilder.com/technical-indicators/momentum/stochastic-rsi/
- Implementation source: https://github.com/IslamBaraka90/Fintech-Algorithms-Library/blob/main/src/technical-indicators/momentum/stochastic-rsi/impl.ts
- Package on npm: https://www.npmjs.com/package/fintech-algorithms
- Domain index for agents: https://docs.thefintechbuilder.com/technical-indicators/llms.txt