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How to increase font size in the legend of your chart.js plot?

I am trying to increase labels' font size in the legend of a plot that I have done with chart.js.
Attached there is a screenshot:
I want to increase the font size of "Label 1,2,3".
Below the javascript configuration that I am using right now:
var data = {
labels: x_axis_labels,
datasets: [
{
label: 'Label 1',
data: data_1,
borderColor: 'rgb(46,138,207)',
backgroundColor: 'rgb(46,138,207)',
yAxisID: 'y',
},
{
label: 'Label 2',
data: data_2,
borderColor: 'rgb(214,224,52)',
backgroundColor: 'rgb(214,224,52)',
yAxisID: 'y1',
},
{
data: data_3,
label:'Label 3',
borderColor: 'rgb(244,67,54)',
backgroundColor: 'rgb(244,67,54)',
yAxisID: 'y1',
pointStyle:'dash',
borderDash: [20, 30],
pointBackgroundColor: "transparent",
},
]
};
const config = {
type: 'line',
data: data,
options: {
responsive: true,
interaction: {
mode: 'index',
intersect: false,
},
stacked: false,
plugins: {
title: {
display: true,
}
},
scales: {
x:{
title:{
display: true,
text: 'X axis name',
font: {size:30},
},
ticks: {
font: {
size: 20,
}
}
},
y: {
title:{
display: true,
text: 'First y axis name',
font: {size:30}
},
type: 'linear',
display: true,
position: 'left',
ticks: {
font: {
size: 24,
}
}
},
y1: {
title:{
display: true,
text: 'Second Y axis name',
font: {size:30}
},
type: 'linear',
display: true,
position: 'right',
ticks:{
font:{
size:24,
}
},
// grid line settings
grid: {
drawOnChartArea: false,
},
},
},
},
};
I have tried Font Documnetation and Legend Documentation but I got nothing.
Someone had experience in this?
Thanks in advance

As described in the docs you can set the size in the options.plugins.legend.labels.font.size namespace
options: {
plugins: {
legend: {
labels: {
font: {
size: 20
}
}
}
}
}

chartjs-plugin-datalabels not showing on stacked horizontal bar

I'm trying to make a simple horizontal stacked bar chart and add labels to it. I'm not sure what I'm doing wrong here, any input would be appreciated.
I can make it work by downgrading to a much lower version of chart.js and the datalabel plugin.
Here is a jsfiddle:
https://jsfiddle.net/chrispret/szLgyu2j/24/
And some test code...
const testData = {
set1: '4',
set2: '3',
set3: '1',
set4: '3',
};
const data = {
labels: ["test"],
datasets: [
{
label: 'set1',
data: [testData.set1],
backgroundColor: 'red',
datalabels: {
anchor: 'center',
align: 'center',
}
},
{
label: 'set2',
data: [testData.set2],
backgroundColor: 'blue',
datalabels: {
anchor: 'center',
align: 'center',
}
},
{
label: 'set3',
data: [testData.set3],
backgroundColor: 'green',
datalabels: {
anchor: 'center',
align: 'center',
}
},
{
label: 'set4',
data: [testData.set4],
backgroundColor: 'gray',
datalabels: {
anchor: 'center',
align: 'center',
}
}
]
};
const config = {
type: 'bar',
data: data,
options: {
aspectRatio: 15 / 3,
indexAxis: 'y',
elements: {
bar: {
borderWidth: 2,
}
},
responsive: true,
scales: {
x: {
stacked: true,
},
y: {
stacked: true
}
},
plugins: {
datalabels: {
color: 'white',
font: {
weight: 'bold'
},
formatter: Math.round
},
legend: {
position: 'right',
},
title: {
display: true,
text: 'Chart.js Horizontal Bar Chart'
},
}
},
};
const myChart = new Chart(
document.getElementById('chartDemo'),
config
);

Since version 1.x, the chartjs-plugin-datalabels plugin no longer registers itself automatically. It must be manually registered either globally or locally as described here.
Therefore, to make it work, you could add the following line to your code prior to create the chart.
Chart.register(ChartDataLabels);
Please take a look at your amended code and see how it works.
const testData = {
set1: '4',
set2: '3',
set3: '1',
set4: '3',
};
const data = {
labels: ["test"],
datasets: [{
label: 'set1',
data: [testData.set1],
backgroundColor: 'red'
},
{
label: 'set2',
data: [testData.set2],
backgroundColor: 'blue'
},
{
label: 'set3',
data: [testData.set3],
backgroundColor: 'green',
datalabels: {
anchor: 'center',
align: 'center'
}
},
{
label: 'set4',
data: [testData.set4],
backgroundColor: 'gray'
}
]
};
const config = {
type: 'bar',
data: data,
options: {
aspectRatio: 15 / 3,
indexAxis: 'y',
elements: {
bar: {
borderWidth: 2
}
},
responsive: true,
scales: {
x: {
stacked: true
},
y: {
stacked: true
}
},
plugins: {
datalabels: {
anchor: 'center',
align: 'center',
color: 'white',
font: {
weight: 'bold'
},
formatter: Math.round
},
legend: {
position: 'right'
},
title: {
display: true,
text: 'Chart.js Horizontal Bar Chart'
},
}
},
};
Chart.register(ChartDataLabels);
const myChart = new Chart(
document.getElementById('chartDemo'),
config
);
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.7.0/chart.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/chartjs-plugin-datalabels/2.0.0/chartjs-plugin-datalabels.min.js"></script>
<canvas id="chartDemo"></canvas>

Add the labels to the labels array.
const data = {
labels: ["hrZone1","hrZone2","hrZone3","hrZone4"],
datasets: [
{
label: 'peak',
data: [hrData.peak,0,0,0],
backgroundColor: 'red'
},
{
label: 'cardio',
data: [0,hrData.cardio,0,0],
backgroundColor: 'blue'
},
{
label: 'fatBurn',
data: [0,0,hrData.fatBurn,0],
backgroundColor: 'green'
},
{
label: 'under',
data: [0,0,0,hrData.under],
backgroundColor: 'gray'
}
]
};

Data Labels wrongly positioned on bar chart - chartjs

I'm using chartjs-plugin-datalabels to show values on chart, but the labels are not centered.
The main part is in the datasets.datalabels where I can override default settings, which sets to center anyway, but wanted to show where its done.
I have tried positione it to the right, but as the value getting bigger, the datalabel is less centered.
Chart.register(ChartDataLabels);
const data_tafkidim_cat_count = {
labels: window.TafkidimCatCount.map((el) => el.TafkidCat.split(' ')).slice(0, pagination['tafkidim_cat_count'].show),
datasets: [
{
data: window.TafkidimCatCount.map((el) => el.Total),
backgroundColor: Setcolors(),
borderColor: Setcolors(1),
borderWidth: 1,
datalabels: {
anchor: 'center',
align: 'center',
},
},
],
};
const config_tafkidim_cat_count = {
type: 'bar',
data: data_tafkidim_cat_count,
options: {
scales: {
x: {
grid: {
borderColor: '#829AB1',
},
ticks: {
color: '#627D98',
},
reverse: true,
},
y: {
grid: {
borderColor: '#829AB1',
},
beginAtZero: true,
ticks: {
color: '#627D98',
},
},
},
plugins: {
title: {
text: TL['tafkidim_cat_count'],
padding: {
bottom: 20,
},
},
legend: {
display: false,
},
tooltip: {
callbacks: {
title: (context) => {
return context[0].label.replaceAll(',', ' ');
},
},
},
},
},
};
const tafkidim_cat_count = new Chart('#tafkidim-cat-count'.Element().getContext('2d'), config_tafkidim_cat_count);

solved it with
textAlign = "center"
apparently the default is "start".

Highcharts zones feature for imported text file

I'm trying to have zones within my graph that change color when the value exceeds a particular threshold.
Here is my graph:
The Highchart resources have an example for how to do this:
https://jsfiddle.net/gh/get/library/pure/highcharts/highcharts/tree/master/samples/highcharts/series/color-zones-simple/
My problem however, is that I can't find an example anywhere for how to do it when your Highchart is importing the data from a text file.
I've styled my chart pretty heavily so this is my highchart code snippet:
$(function () {
// Load the fonts
Highcharts.createElement('link', {
href: 'http://fonts.googleapis.com/css?family=Signika:400,700',
rel: 'stylesheet',
type: 'text/css'
}, null, document.getElementsByTagName('head')[0]);
// Add the background image to the container
Highcharts.wrap(Highcharts.Chart.prototype, 'getContainer', function (proceed) {
proceed.call(this);
this.container.style.background =null;
});
Highcharts.theme = {
colors: ['#5B8256'],
chart: {
backgroundColor: null,
style: {
fontFamily: "Arial, Helvetica, sans-serif"},
plotBorderColor: '#606063'},
title: {
style: {
color: '#eeeeee',
fontSize: '16px',
fontWeight: ''}},
subtitle: {
style: {
color: '#eeeeee'}},
tooltip: {
backgroundColor: 'rgba(0, 0, 0, 0.85)',
style: {color: '#F0F0F0'},
borderWidth: 0},
legend: {
itemStyle: {
fontWeight: 'bold',
fontSize: '13px'}},
xAxis: {
labels: {
style: {
color: '#eeeeee'}}},
yAxis: {
labels: {
style: {
color: '#eeeeee'}}},
plotOptions: {
series: {shadow: true},
marker: {lineColor: '#333'},
candlestick: {lineColor: '#404048'},
map: {shadow: false}},
navigator: {
xAxis: {gridLineColor: '#D0D0D8'}},
rangeSelector: {
buttonTheme: {fill: '#eeeeee',stroke: '#C0C0C8','stroke-width': 1,
states: {
select: {fill: '#D0D0D8'}}}},
scrollbar: {trackBorderColor: '#eeeeee'},
background2: null};
Highcharts.setOptions(Highcharts.theme);
var options = {
chart: {
zoomType: 'x',
renderTo: 'container',
defaultSeriesType: 'column',
resetZoomButton: {
theme: {display: 'none'}}},
title: {
text: 'Max Pressure Today:',
style: {
fontSize: '14px',opacity: 0,
style: {color: '#'}}},
xAxis: {type: 'datetime'},
yAxis: [{ // Primary yAxis
labels: {format: '{value}',
style: {color: '#eeeeee'}},
title: {
text: '',
style: {color: '#1E1E1E'}},
opposite: false},],
legend: {enabled: false},
tooltip: {shared: true,valueSuffix: ' psi'},
plotOptions: {
column: {pointPadding: 0.2,borderWidth: 0},
series: {name: 'Pressure',pointStart: Date.UTC(2016, 10, 7),pointInterval: 12 * 3600 * 1000}},
series: []};
$.get('demo-data.txt', function(data) {
var lines = data.split('\n');
lines = lines.map(function(line) {var data = line.split(',');
data[1] = parseFloat(data[1]);return data;});
var series = {data: lines};
options.series.push(series);
var chart = new Highcharts.Chart(options);});});
Any help pointing me in the right direction would be appreciated.

You can add zones by plot-options, for example:
plotOptions: {
series: {
zones: [{
value: 20,
color: '#7cb5ec'
}, {
color: '#90ed7d'
}],
...
}
}
Live demo: https://jsfiddle.net/BlackLabel/5w9rvonz/
API Reference: https://api.highcharts.com/highcharts/plotOptions.series.zones

How to create in a series multiple data each in a different yaxis using highcharts

I'm working on a project to register pump curves in a MySQL database. So I'm trying to create the closest possible one chart with 3 yAxis (H, NPSH, Power) and 2 xAxis (flow and efficiency). I uploaded a pump curve image here for better understanding. Note this efficiency is a logarithm scale but I prefer to create a linear scale to make it easy.
Well, every curve chart has more one rotor curve, in this case we have 5 curves which is five types of rotor (176mm, 169mm, 162mm, 154mm and 148mm).
Each rotor gives one data series in a yAxis as H, NPSH, Power and Efficiency.
So I need to create a series for each rotor size whem each series get the values ​​of the data: H,NPSH,Power,Efficiency with its yAxis referals.
Here is the link's page with the code.
$(function () {
$('#container').highcharts({
chart: {
zoomType: 'xy'
},
title: {
text: 'Curva da Bomba'
},
subtitle: {
text: 'KSB Meganorm 32-160 | Rotação 1750rpm'
},
xAxis: [{
tickmarkPlacement: 'on',
labels: {
format: '{value}m³/h',
style: {
color: '#005ca2'
}
},
title: {
text: 'Vazão Q (m³/h)',
style: {
color: '#005ca2'
}
}
},{// Rendimento
labels: {
format: '{value}%',
style: {
color: '#005ca2'
}
},
title: {
text: 'Rendimento n (%)',
style: {
color: '#005ca2'
}
},
opposite: true,
top: 90,
height: 0,
offset: 0,
lineWidth: 1
}],
yAxis: [{ // Altura manométrica H
labels: {
format: '{value}mca',
style: {
color: '#005ca2'
}
},
title: {
text: 'Altura manométrica H (mca)',
style: {
color: '#005ca2'
}
},
top: 90,
height: 250,
offset: 0,
lineWidth: 1
}, { // NPSH
labels: {
format: '{value}mca',
style: {
color: '#005ca2'
}
},
title: {
text: 'NPSH (mca)',
style: {
color: '#005ca2'
}
},
top: 380,
height: 120,
offset: 0,
lineWidth: 1
}, {// Potência
title: {
text: 'Potência (hp)',
style: {
color: '#005ca2'
}
},
labels: {
format: '{value} hp',
style: {
color: '#005ca2'
}
},
top: 540,
height: 220,
offset: 0,
lineWidth: 1
}],
tooltip: {
crosshairs: true,
shared: true
},
legend: {
layout: 'horizontal',
align: 'center',
x: 0,
verticalAlign: 'top',
y: 34,
floating: true,
backgroundColor: '#FFFFFF'
},
plotOptions: {
spline: {
lineWidth: 3,
states: {
hover: {
lineWidth: 4
}
},
marker: {
enabled: false
},
pointInterval: 1, // one hour
pointStart: 6
}
},
series: [{
name: 'Rendimento n (Rotor 176mm)',
color: '#FF0000',
type: 'spline',
data: [40,44,45.5,48,50,51.5,52.5,53,53.8,54.7,54.6,53.4,53.4,52.5],
dashStyle: 'shortdot',
tooltip: {
valueSuffix: '%'
}
}, {
name: 'Pressão H (Rotor 176mm)',
color: '#FF0000',
type: 'spline',
data: [14.1,13.9,13.7,13.45,13.2,12.8,12.45,12.1,11.65,11.3,10.7,10.27,9.8,9.2],
tooltip: {
valueSuffix: 'mca'
}
}, {
name: 'NPSH (Rotor 176mm)',
color: '#FF0000',
type: 'spline',
yAxis: 1,
data: [1.2,1.25,1.3,1.4,1.4,1.4,1.4,1.4,1.4,1.63,1.78,2.5,3.2,4],
tooltip: {
valueSuffix: 'mca'
}
}, {
name: 'Potência (Rotor 176mm)',
color: '#FF0000',
type: 'spline',
yAxis: 2,
data: [0.8,0.87,0.92,0.96,1.01,1.04,1.08,1.13,1.15,1.19,1.22,1.24,1.26,1.29],
tooltip: {
valueSuffix: 'hp'
}
}]
});
});

You can set which yAxis a series is plotted against by using the yAxis: <index> value in the series setup. For example:
...
{
name: 'Pressão H (Rotor 176mm)',
color: '#FF0000',
type: 'spline',
data: [14.1,13.9,13.7,13.45,13.2,12.8,12.45,12.1,11.65,11.3,10.7,10.27,9.8,9.2],
tooltip: {
valueSuffix: 'mca'
},
yAxis: 1,
}
...
Here is a very quick example of it. You have 2 xAxis and 3 yAxis. No idea if this is how you want to display it but this shows you how to move the axis around.