---
title: "Market Heatmap API: Treemap Heatmaps as Images - Imejis.io"
description: "Market heatmap API: render treemap heatmaps of sectors, tickers, or portfolios as PNG or SVG from one endpoint. For daily Slack drops, email digests, and social graphics."
url: "https://www.imejis.io/market-heatmap-api"
image: "https://www.imejis.io/og.png"
---

# Market Heatmap API: Treemap Heatmaps as Images - Imejis.io

Market Heatmap API

# Market heatmaps as images

Render treemap heatmaps of sectors, tickers, or portfolios, sized by weight and colored by performance, as PNG or SVG from one endpoint. Perfect for a daily Slack or email drop.

[Start free](https://app.imejis.io)[Read the API docs](/apis)

## The treemap does the heavy lifting

Rectangle size shows weight, color shows performance: a whole market at a glance. Pair it with charts and metric tiles for a full recap card. Live previews below.

[treemap](/components/treemap)[chart](/components/chart)[candlestick](/components/candlestick)[metric](/components/metric)[table](/components/table)

[See all 24 chart & data components](/components)

## From data to image in one call

1

### Design a heatmap template

Style a treemap in the editor: size metric, color scale, labels, branding. Then mark the data dynamic.

2

### Send your market data

POST each cell's label, size (weight/market cap), and value (% change) as field overrides. No config JSON to hand-write.

3

### Get a heatmap image back

The response is a finished heatmap with a permanent URL, ready for a Slack channel, an email, or a social post.

## What people render

### Daily market heatmap to Slack

Auto-post a sector or index heatmap every morning so the whole team sees the market at a glance.

### Newsletter & email recaps

Email strips scripts, so interactive heatmaps break. An image renders for every subscriber.

### Sector & index performance

One treemap that shows which sectors led and lagged, sized by weight and colored by return.

### Portfolio heatmaps

Render a per-user portfolio heatmap, positions sized by allocation and colored by P&L.

### Crypto market maps

A heatmap of the top coins by market cap and 24h change, for a channel or a landing page.

### Automated reporting

Wire it to your market data source and generate a fresh heatmap image on every run.

## Why an image heatmap?

### Interactive JS heatmaps

Great in a browser, but they don't render in email, Slack, a PDF, or an OG tag.

A static image URL works in every one of those places.

### Headless-browser screenshots

Run and scale Chromium and a viz library just to snapshot one treemap.

Send the data, get the heatmap image. Nothing to host or babysit.

### Config-driven chart APIs

Limited treemap support, dated defaults, and hand-written JSON config.

A visual editor, an on-brand template, and the same heatmap on tap via API.

## Keep exploring

[Market heatmap to Slack (guide)](/blogs/use-cases/market-heatmap-to-slack)[Treemap chart maker (free tool)](/tools/treemap-generator)[Chart Image API (all chart types)](/chart-image-api)[All 24 chart & data components](/components)

## Market Heatmap API FAQs

### What is a market heatmap API?

It renders a market heatmap, a treemap where rectangle size shows weight and color shows performance, as a static image (PNG or SVG) from data you send over HTTP. You use it wherever an interactive heatmap can't run: email, Slack, a PDF, or an OG tag.

### Is it a treemap under the hood?

Yes. The treemap component sizes each cell by a weight metric (market cap, allocation, volume) and colors it by a value (percent change, P&L), which is exactly what a market heatmap needs.

### Can I post it to Slack automatically?

Yes. Generate the heatmap image on a schedule and post its URL to a Slack channel via a workflow or a bot. See the market-heatmap-to-Slack guide for a full walkthrough.

### Does it work for crypto or portfolios?

Yes. The data is just label + size + value per cell, so it works for equities, sectors, crypto, or a per-user portfolio heatmap.

### Is there a free tier?

Yes. 100 renders per month, permanently, with no watermark. Paid plans start at $14.99/mo for 1,000 renders and scale to a $0.70 effective cost per 1,000 on the Unlimited plan.

## Render your first heatmap in minutes

Start on the free tier. 100 renders a month, no watermark, no card.

[Start free](https://app.imejis.io)[or see pricing](/pricing)

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