Render Any Chart to a PNG From Your Backend

# pip install rendex
from rendex import Rendex
from pathlib import Path

rendex = Rendex("YOUR_API_KEY")

# The same Chart.js markup your frontend uses. Turn the entry animation off so
# the render is deterministic, and give the canvas a moment to paint with delay.
chart_html = """
<canvas id="c" width="640" height="360"></canvas>
<script src="https://cdn.jsdelivr.net/npm/chart.js@4"></script>
<script>
  new Chart(document.getElementById("c"), {
    type: "bar",
    data: {
      labels: ["Q1", "Q2", "Q3", "Q4"],
      datasets: [{ label: "Revenue (€M)", data: [1.24, 1.41, 1.55, 1.78] }],
    },
    options: { animation: false, responsive: false },
  });
</script>
"""

result = rendex.render_html(
    chart_html, format="png", device_scale_factor=2, delay=1500,
)
Path("revenue-chart.png").write_bytes(result.image)
# -> embed result.image in your PDF report, email, or Slack message

# pip install rendex
from rendex import Rendex

rendex = Rendex("YOUR_API_KEY")

# Render every chart on a dashboard in parallel instead of blocking a worker
# on N sequential renders. Each chart is its own self-contained HTML string.
charts = [revenue_html, churn_html, runway_html]  # each draws one chart
images = [
    rendex.render_html(c, format="png", device_scale_factor=2, delay=1500).image
    for c in charts
]
# Assemble images[...] into your report deliverable or email.

curl -X POST https://api.rendex.dev/v1/screenshot \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "html": "<canvas id=\"c\"></canvas><script src=\"https://cdn.jsdelivr.net/npm/chart.js@4\"></script><script>/* draw chart */</script>",
    "format": "png",
    "deviceScaleFactor": 2,
    "waitForSelector": "#c",
    "delay": 1500
  }' --output chart.png