Limits and Quotas on API Requests

This document describes the limits and quotas of requesting the Image-Charts API.

Image-Charts is used by millions of sites. We put limits and quotas on chart generation requests to protect the system from receiving more data than it can handle, and to ensure an equitable distribution of the system resources. The limits and quotas are subject to change.

General quota limits

The following quotas apply to Image-Charts API;

• 90 queries per 10 seconds per IP address (thus 9 queries per second (QPS))

tip

Please contact our support team if you have special needs.

Free API usage quota limits

The following quotas apply to Image-Charts API calls without authentication (ichm and icac)

• 10 queries per 1 minute per IP address

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If you wish to get higher throughput please subscribe.

Exceeding quota limits

If the quota of requesting Image-Charts API is exceeded, the API returns an error code 429 and a message that the account has exceeded the quota. When the threshold is met, the client will be blocked for 1 minute.

Chart complexity limits

The API limits how many series, points, texts and ticks a chart can hold. A request over a limit gets:

• the 400 HTTP status code
• the IS_VALIDATION_ERROR error code in the x-ic-error-code response header
• the reason in the x-ic-error-validation response header, as a JSON list of messages

A message names the limit that was exceeded and how to stay under it:

x-ic-error-code: IS_VALIDATION_ERROR
x-ic-error-validation: [{"message":"The chart has 1001 series, more than 1000. Merge some of them.","path":[],"context":{},"type":"IS_VALIDATION_ERROR"}]

GET and POST /chart

GET /chart and POST /chart take the same parameters and apply the same limits.

Parameter	Limit	How to stay under it
chd and chm	At most 1,000 series. A D line marker of chm draws a series of its own and counts as one.	Merge series.
chd and chm	At most 10,080 points over all series. This is one week at one point per minute.	Aggregate or sample your data.
chtt, chdl, chl and chxl	At most 10,000 characters per text. Pipe characters separate the texts of one parameter.	Shorten the text.
chxs and chm	At most 10,000 characters per number format. In chxs the format follows the N after the axis index. In chm it follows the N of an N marker.	Shorten the format.
chm	An N marker draws its format at each point of its series. The format length times the number of points, added up over all N markers, is at most 500,000 characters.	Shorten the format, or send fewer points.
chxs	An axis draws its format at each tick. The format length times the number of ticks, added up over all axes, is at most 800,000 characters. An axis counts at least as many ticks as the longest series has points, up to 11,000.	Shorten the format, or send fewer points.
chls	On a line chart, the dash and the space of a dashed line average at least 1 pixel.	Lengthen the dash and the space.
chls	The thickness of a dashed line is at most twice the length of its dash plus its space.	Lengthen the dash and the space, or thin the line.
chls	The series drawn with a dashed line hold at most 1,000 points together.	Send fewer points, or leave out the dash and space lengths to draw solid lines.
chg	The dash and the space of a dashed grid average at least 1 pixel.	Lengthen the dash and the space.

chl has no text limit on a QR code or a Graphviz chart. These charts read chl as their data.

Some examples of how to stay under a limit:

• An N marker with a 60-character format on a series of 10,000 points would draw 600,000 characters, so it is refused. A 50-character format draws exactly 500,000 characters and is accepted.
• A chxs format of 100 characters on a chart whose longest series holds 10,000 points would draw 1,000,000 characters. A format of 80 characters draws 800,000 and is accepted.
• chls=10,1,1 is refused. A 10 pixel line needs a dash plus a space of at least 5 pixels. chls=10,3,2 is accepted.

GET /chart.js

These limits apply to the Chart.js configuration sent in the c (or chart) parameter. The limits of width and height are in Chart size. The limits on ticks are in Axis ticks.

Configuration	Limit	How to stay under it
Nesting	Objects and arrays nest at most 64 levels below the root object.	Flatten the configuration.
options.scales.xAxes and options.scales.yAxes	At most 20 axes over both lists.	Remove axes, or share them between datasets.
data.labels, data.xLabels and data.yLabels	At most 10,000 labels in each list.	Aggregate the data into fewer labels.
data.datasets	At most 1,000 datasets.	Merge datasets.
data of the datasets	At most 10,000 points over all datasets.	Aggregate or sample the data.
Texts	At most 10,000 characters per text value, wherever it sits in the configuration.	Shorten the text.
borderWidth, hoverBorderWidth, pointBorderWidth, pointHoverBorderWidth, lineWidth, zeroLineWidth, radius, hoverRadius, pointRadius and pointHoverRadius	At most 50 pixels, wherever the option sits. When the value is a list or an object, each number in it is checked.	Lower the value.
padding	At most 100 pixels.	Lower the value.
minRotation and maxRotation	From -360 to 360 degrees.	Use an angle within one turn.
borderDash and zeroLineBorderDash	At most 16 entries. The entries average at least 1 pixel.	Use a shorter pattern, or lengthen its entries.
borderDash and zeroLineBorderDash	The line width is at most twice the length of the pattern. The length is the sum of the entries, counted twice for an odd number of entries. A line without a width counts as 3 pixels for a dataset line and 1 pixel for a grid line or an angle line.	Lengthen the pattern, or thin the line.
Datasets with a borderDash	The dashed datasets hold at most 1,000 points together.	Send fewer points, or draw the lines solid.
datalabels	At most 10 entries in labels per dataset. The entries of options.plugins.datalabels.labels count for every dataset, next to those of the dataset.	Name fewer labels.
datalabels with display set to 'auto'	The number of points times the number of labels entries is at most 3,000 over all datasets. A dataset without labels entries counts one label per point.	Show fewer labels, or set display to true.
Radial scale (options.scale)	At most 1,000 labels when the scale displays its angleLines or its pointLabels. Each label draws a spoke.	Send fewer labels, or hide angleLines and pointLabels.
Radial scale (options.scale)	The rings (one per tick) times the spokes (one per label) make at most 100,000 corners, unless gridLines.circular is set.	Raise ticks.stepSize, send fewer labels, or set gridLines.circular.

Data format

If the configuration has a data key, data.datasets must be a list of objects. The first dataset must hold a data array. Otherwise the answer is a 400 with the IC_BAD_DATA_FORMAT error code. A null data and a null dataset are refused this way.

Arrays

data.labels, data.xLabels, data.yLabels, options.scales.xAxes, options.scales.yAxes and the data of each dataset after the first must be JSON arrays. An object in their place is refused with the IS_VALIDATION_ERROR error code. So is any object that holds a key named length, wherever it sits in the configuration.