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Charts from data

CSV to Gantt chart online

Three columns — a task, a start date and an end date — become a project timeline. Each bar spans the days the task occupies, and overlapping bars show at a glance which work runs in parallel. No account, no project file, no upload.

Your data never leaves this device

Your data

Paste a table straight from Excel or Google Sheets, or drop a CSV file. Nothing is uploaded anywhere — the whole calculation runs inside this browser tab.

CSV, TSV or plain text. Files saved in windows-1251 are detected and re-read automatically, so Cyrillic headers do not turn into garbage.

Parsing options

Columns

Result

The drawing library is downloaded only when you press the button, and only on this page.

This page has no server side at all. The table you paste is parsed by JavaScript inside your own browser, the chart is drawn on a canvas element on your machine, and the export file is assembled locally. Nothing is uploaded, stored or written to any log. You can disconnect from the network after the page has loaded and everything will still work — which is the simplest way to verify the claim yourself.

Facts and limits of this method

Input Three columns: task name, start date, end date
Date formats accepted ISO 2026-09-01, European 01.09.2026, US 09/01/2026
Ambiguous dates When both numbers are ≤ 12, the first is read as the day (European convention)
Duration Inclusive of both endpoints — a task from the 1st to the 1st lasts one day
Reversed rows Handled: if the end precedes the start, the two are swapped
Output PNG at 2× scale, plus CSV with normalised ISO dates and durations in days

When it misleads you

How it is calculated

Dates are parsed from three formats: ISO, dot-separated European and slash-separated US. When a date is genuinely ambiguous — both numbers twelve or less — the first number is read as the day, because that is the convention across the four languages this section is published in.

The horizontal axis is a linear count of days from the earliest date in your table, with the ticks relabelled as calendar dates. Doing it this way rather than with a real time scale avoids pulling in a date adapter and its dependency, which would double the size of the chart library on this page.

Durations are inclusive of both endpoints, so a task running from the 1st to the 5th lasts five days rather than four. That is what people mean when they write those dates in a plan, even though it is not what subtracting them gives.

Rows with an unparseable date are skipped and counted, and the count is reported under the chart. If every row fails, the tool says so explicitly instead of drawing an empty canvas.

Questions and answers

Which date formats work?

ISO (2026-09-01), European with dots (01.09.2026) and US with slashes (09/01/2026). Mixed formats in one table are fine — each cell is parsed on its own.

Is 03/04/2026 the third of April or the fourth of March?

This tool reads it as the third of April: when both numbers could be a month, the first is treated as the day. If your file uses the US convention, convert it to ISO first to remove the ambiguity entirely.

Can I add dependencies between tasks?

No. This draws a timeline, it does not schedule one. Dependencies, critical paths and automatic rescheduling belong to project management software.

Why is my one-day task showing as one day when the dates are identical?

Because durations include both endpoints. A task from the 1st to the 1st occupies one day, which matches how the dates are meant when someone writes them in a plan.

Is my project plan uploaded anywhere?

No. Dates are parsed and the chart is drawn inside your browser; nothing about the project leaves your machine.

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