How to Make a Chart Online for Free (Bar, Line, Pie — No Signup)

You can create bar charts, line charts, and pie charts from any data using brevio Chart Maker — enter your data as "Label,Value" pairs, pick a chart type, and download as PNG instantly. No account, no upload, all rendering happens in your browser via the Canvas API.

Charts communicate data faster than tables. A table of monthly sales figures across 12 rows requires the reader to scan and compare numbers mentally. The same data as a bar chart communicates the trend, the peaks, and the outliers in under a second. Choosing the right chart type for your data is the first and most important step.

When to Use Each Chart Type

Bar charts are best for comparing discrete categories. Use them when your question is "which is larger?" — product sales by category, survey results across options, performance by team. Bars make it easy to rank and compare at a glance. Vertical bars (the default) work best for categories; horizontal bars work better when you have many categories with long labels.

Line charts are best for showing trends over time or across ordered categories. Use them when your question is "how did this change?" — monthly revenue over a year, daily active users over a launch period, temperature across hours of the day. Lines imply continuity between points — don't use them for unrelated categories (use bars instead).

Pie charts are best for showing proportions that sum to a meaningful whole. Use them when your question is "what share of the total?" — market share breakdown, budget allocation, survey sentiment split. Pie charts work well with 3–5 categories; more than that and the slices become too small to read. Always include percentage labels — raw numbers on pie charts are harder to interpret than proportions.

Data Format Guide

brevio Chart Maker expects one data point per line in "Label,Value" format. Labels can contain spaces. Values must be numbers (integers or decimals). Empty lines are ignored. Lines that don't match the format (no comma, non-numeric value) are silently excluded — the valid row count shows how many points were parsed.

// Correct format
Q1 Revenue,125000
Q2 Revenue,148000
Q3 Revenue,132000
Q4 Revenue,167000

// Will be ignored (no comma, or non-numeric value)
Header Line
Invalid,abc

Accessibility: Alt Text for Charts

When using chart images in documents, web pages, or presentations, always include a text description (alt text) for screen reader users. A good chart alt text summarises the key insight, not just the chart title. Instead of "Bar chart of monthly revenue", write "Bar chart showing revenue increasing from $125K in January to $167K in December, with a dip in March".

For web use, the HTML alt attribute: <img src="chart.png" alt="Bar chart: Q4 revenue ($167K) was highest; Q1 ($125K) lowest. Overall trend upward across the year.">. In PowerPoint and Google Slides, right-click the image and use "Alt Text" to add a description.

Chart Maker Comparison

Frequently Asked Questions

What resolution is the downloaded PNG?

The canvas renders at 600×400 pixels. For screen use (presentations, social media, web pages) this is sufficient. For large print output, you will need a higher-resolution tool — Canva or Adobe Illustrator for vector export that scales without pixelation.

Can I use more than 6 data points?

Yes — there is no hard limit on data points. However, charts become harder to read with many categories. For bar and line charts, 10–12 data points is practical. For pie charts, 5–6 segments is a usability limit — more than that and slices become too small to read meaningfully.

Why does my line chart look wrong with non-time data?

Line charts imply continuity between adjacent points. If your categories are not ordered or continuous (e.g., product types, countries), a line connecting them suggests a relationship that doesn't exist. Use a bar chart for categorical data that isn't a time series.

Can I change the chart colours?

The current version uses a fixed 6-colour palette cycling through data points. Custom colour selection is not available in this version. For custom branded charts, Canva or Chart.js give full colour control.