How do I create a candlestick chart in JavaScript?

Install with `npm install katucharts.js`, import the module with `import 'katucharts.js/finance';`, then call KatuCharts.chart(container, { chart: { type: 'candlestick' }, series: [...] }).

Why does my candlestick chart render as a line chart?

The chart type was not registered. KatuCharts logs "KatuCharts: unknown series type " ", falling back to line" and draws a line chart rather than throwing. Import the module the type belongs to — for example `import 'katucharts.js/bio';` — before creating the chart.

Why do I get "Cannot read properties of null (reading 'appendChild')"?

The container element does not exist when the chart is created. Create the chart after the element is in the DOM: in React that means inside useEffect, not during render.

Why is the chart rendering with zero height?

The container has no height. A div with no content collapses to zero. Give it a height in CSS, or pass `chart: { height: 400 }` in the options.

Financial · katucharts.js/finance

Candlestick

type: 'candlestick'

OHLC candlestick chart for time series. Filled body for bearish candles (close < open), hollow for bullish; wicks show the high/low range.

Edit the JSON on the right and press Run (or ⌘/Ctrl + Enter) — data, titles, categories and colors all update live.

Live

Candlestick

Edit · JSON

{
  "chart": {
    "type": "candlestick"
  },
  "title": {
    "text": "KATU Weekly"
  },
  "xAxis": {
    "categories": [
      "W1",
      "W2",
      "W3",
      "W4",
      "W5",
      "W6",
      "W7",
      "W8",
      "W9",
      "W10"
    ]
  },
  "series": [
    {
      "name": "KATU",
      "color": "#1B1A15",
      "upColor": "#B43417",
      "lineColor": "#1B1A15",
      "upLineColor": "#B43417",
      "data": [
        [
          172,
          178,
          170,
          176
        ],
        [
          176,
          182,
          174,
          180
        ],
        [
          180,
          185,
          178,
          177
        ],
        [
          177,
          183,
          175,
          182
        ],
        [
          182,
          190,
          180,
          188
        ],
        [
          188,
          192,
          185,
          186
        ],
        [
          186,
          191,
          183,
          190
        ],
        [
          190,
          198,
          188,
          196
        ],
        [
          196,
          200,
          192,
          194
        ],
        [
          194,
          202,
          191,
          199
        ]
      ]
    }
  ]
}

Data format

{ x: timestamp, open, high, low, close } · [[o,h,l,c]]

Data shape

The JSON you pass inside the chart — drop it straight into your series.

data: [
  [172, 178, 170, 176],
  [176, 182, 174, 180],
  [180, 185, 175, 181]
]

Example

import KatuCharts from 'katucharts.js';

KatuCharts.chart('container', {
  chart: { type: 'candlestick' },
  series: [{
    name: 'KATU',
    data: [
      [172, 178, 170, 176],
      [176, 182, 174, 180],
      [180, 185, 175, 181]
    ]
  }]
});

Type-specific options

Option	Description
`upColor`	Bullish candle body color (close > open).
`color`	Bearish candle body color.
`lineColor / upLineColor`	Wick & border stroke / bullish wick override.

Variations

With moving average

Overlay an SMA indicator on the price series with type + linkedTo.

import KatuCharts from 'katucharts.js';
import 'katucharts.js/finance';

KatuCharts.chart('container', {
  chart: { type: 'candlestick' },
  series: [
    { id: 'px', name: 'KATU', data: ohlc },
    { type: 'sma', linkedTo: 'px', params: { period: 5 } }
  ]
});

Common errors

Why does my candlestick chart render as a line chart?: The chart type was not registered. KatuCharts logs "KatuCharts: unknown series type "<type>", falling back to line" and draws a line chart rather than throwing. Import the module the type belongs to — for example `import 'katucharts.js/bio';` — before creating the chart.
Why do I get "Cannot read properties of null (reading 'appendChild')"?: The container element does not exist when the chart is created. Create the chart after the element is in the DOM: in React that means inside useEffect, not during render.
Why is the chart rendering with zero height?: The container has no height. A div with no content collapses to zero. Give it a height in CSS, or pass `chart: { height: 400 }` in the options.

FAQ

How do I create a candlestick chart in JavaScript?: Install with `npm install katucharts.js`, import the module with `import 'katucharts.js/finance';`, then call KatuCharts.chart(container, { chart: { type: 'candlestick' }, series: [...] }).
Why does my candlestick chart render as a line chart?: The chart type was not registered. KatuCharts logs "KatuCharts: unknown series type "<type>", falling back to line" and draws a line chart rather than throwing. Import the module the type belongs to — for example `import 'katucharts.js/bio';` — before creating the chart.
Why do I get "Cannot read properties of null (reading 'appendChild')"?: The container element does not exist when the chart is created. Create the chart after the element is in the DOM: in React that means inside useEffect, not during render.
Why is the chart rendering with zero height?: The container has no height. A div with no content collapses to zero. Give it a height in CSS, or pass `chart: { height: 400 }` in the options.

Common options (color, visible, marker, dataLabels, animation, events, zones…) apply to every type — see Configuration → series. See it rendered in the gallery.