Custom Gantt Chart Development for Project Management
Planning a project without visualizing tasks on a timeline is a direct path to missed deadlines. Teams spend hours aligning schedules, while resource overload remains unnoticed until the last moment. Developers often face N+1 queries when loading tasks or hydration mismatches in Next.js. We solve this with BFF and Suspense, ensuring smooth chart loading without blocking the main thread.
We develop interactive Gantt charts for websites that show dependencies, progress, and team workload. Our engineers have 10+ years of experience in UI component development and guarantee integration with any stack (React, Vue, Angular, vanilla JS).
A Gantt chart displays project tasks on a timeline: start/end, dependencies, completion progress, and resource overload. A custom solution gives full control over design and performance—for example, rendering 10,000 tasks without lag. Budget savings on maintaining such charts can reach 40% compared to implementing heavy BIM systems. The development cost pays off through flexibility and the absence of unnecessary features.
Why a Custom Gantt Is Better Than a Ready-Made Library?
Ready-made libraries (DHTMLX Gantt, Bryntum Gantt) are good for typical scenarios but often have extra weight and limited customization. Custom development on D3.js or React provides:
- optimization for Core Web Vitals (LCP < 2.5 s);
- any visual effects (animations, themes);
- integration with your existing authorization and data store.
Recently we completed a project for a construction company: they needed a Gantt with resource planning and critical path. The ready-made library didn’t allow custom colors for each contractor, but a custom SVG component fit into their design system in 3 weeks. That solution reduced approval time by 30%.
How to Choose the Right Gantt Library?
The choice depends on task complexity. For simple projects with 50–100 tasks, gantt-task-react—an open-source component with basic drag-and-drop—works well. If you need dependency display and critical path, DHTMLX Gantt is better. For unique designs and high performance (10,000+ tasks), a custom SVG component on D3.js is the way to go. The table below provides recommendations.
| Task Type | Recommended Solution | Timeline |
|---|---|---|
| Up to 50 tasks, simple layout | gantt-task-react | 3–5 days |
| 50–500 tasks, dependencies | DHTMLX Gantt | 1–2 weeks |
| 500+ tasks, non-standard UI | Custom SVG/D3 | from 2 weeks |
Full list of configuration parameters
-
viewMode: Day, Week, Month -
onDateChange: date change handler -
onProgressChange: progress change handler -
TooltipContent: custom tooltip -
listCellWidth: width of the task name column -
ganttHeight: chart height -
todayColor: today highlight color
A Gantt chart reveals the critical path, exposes resource overloads, and allows schedule adjustments in real time. Drag-and-drop simplifies rescheduling, and progress bars show delays. Integration with CRM and task trackers automates data updates.
What Is Included in a Turnkey Solution
| Stage | Result |
|---|---|
| Analytics | Requirements gathering, library or architecture selection |
| Design | Interaction prototype, API specification |
| Implementation | Component layout, backend integration |
| Drag-and-drop | Task move setup, date updates |
| Testing | Unit tests, E2E tests (Cypress), performance check |
| Deployment | Publish on Vercel or upload to CMS |
How We Do It: Tech Stack and Examples
gantt-task-react (open-source)
npm install gantt-task-react
import { Gantt, Task, ViewMode } from 'gantt-task-react';
import 'gantt-task-react/dist/index.css';
interface ProjectTask {
id: string;
name: string;
start: Date;
end: Date;
progress: number;
type: 'task' | 'milestone' | 'project';
dependencies?: string[];
assignee?: string;
}
function ProjectGantt({ tasks, onTaskChange }: {
tasks: ProjectTask[];
onTaskChange: (task: Task) => void;
}) {
const [view, setView] = useState<ViewMode>(ViewMode.Week);
const ganttTasks: Task[] = tasks.map(t => ({
id: t.id,
name: t.name,
start: t.start,
end: t.end,
progress: t.progress,
type: t.type,
dependencies: t.dependencies ?? [],
styles: {
progressColor: t.progress >= 100 ? '#22c55e' : '#3b82f6',
progressSelectedColor: '#1d4ed8'
}
}));
return (
<div>
<div className="gantt-toolbar">
<button onClick={() => setView(ViewMode.Day)}>Day</button>
<button onClick={() => setView(ViewMode.Week)}>Week</button>
<button onClick={() => setView(ViewMode.Month)}>Month</button>
</div>
<Gantt
tasks={ganttTasks}
viewMode={view}
onDateChange={onTaskChange}
onProgressChange={onTaskChange}
locale="en"
listCellWidth="200px"
ganttHeight={400}
todayColor="rgba(59, 130, 246, 0.1)"
TooltipContent={({ task }) => (
<div className="gantt-tooltip">
<strong>{task.name}</strong>
<p>Start: {format(task.start, 'dd.MM.yyyy')}</p>
<p>End: {format(task.end, 'dd.MM.yyyy')}</p>
<p>Progress: {task.progress}%</p>
</div>
)}
/>
</div>
);
}
Custom Gantt on SVG + D3
For specific requirements (unique style, non-standard cells), we create a component on D3.js. Below is a prototype example:
import { scaleTime } from 'd3-scale';
import { timeDay, timeWeek } from 'd3-time';
function CustomGantt({ tasks, startDate, endDate, width = 900 }) {
const timelineWidth = width - 200; // 200px for task names
const rowHeight = 40;
const height = tasks.length * rowHeight + 60;
const xScale = scaleTime()
.domain([startDate, endDate])
.range([0, timelineWidth]);
return (
<svg width={width} height={height}>
{/* Time labels */}
{timeWeek.range(startDate, endDate).map(week => (
<g key={week.toISOString()}>
<line
x1={xScale(week) + 200} y1={0}
x2={xScale(week) + 200} y2={height}
stroke="#e5e7eb" strokeWidth={1}
/>
<text
x={xScale(week) + 204}
y={15}
fontSize={11}
fill="#6b7280"
>
{format(week, 'dd MMM')}
</text>
</g>
))}
{/* Tasks */}
{tasks.map((task, i) => {
const x = xScale(task.start) + 200;
const width = xScale(task.end) - xScale(task.start);
const y = i * rowHeight + 25;
return (
<g key={task.id}>
{/* Name */}
<text x={4} y={y + 14} fontSize={13} fill="#374151"
style={{ cursor: 'pointer' }}>
{task.name.length > 22 ? task.name.slice(0, 22) + '…' : task.name}
</text>
{/* Task bar */}
<rect x={x} y={y} width={width} height={24}
rx={4} fill="#93c5fd" />
{/* Progress */}
<rect x={x} y={y} width={width * (task.progress / 100)} height={24}
rx={4} fill="#3b82f6" />
{/* Percentage */}
{width > 40 && (
<text x={x + width / 2} y={y + 16}
textAnchor="middle" fontSize={11} fill="white">
{task.progress}%
</text>
)}
</g>
);
})}
</svg>
);
}
Drag-and-Drop for Changing Dates
When using DHTMLX Gantt, drag-and-drop is built in. For a custom SVG, we use d3-drag or @dnd-kit. Our experience shows that @dnd-kit is more stable with React 18.
Step-by-Step Guide to Integrating a Gantt Component
-
Install dependencies. For gantt-task-react:
npm install gantt-task-react date-fns. For D3:npm install d3-scale d3-time. - Create the component. Define a task interface and pass the array of tasks to the Gantt.
-
Set up handlers. Implement
onDateChangeandonProgressChangefor backend synchronization. - Add tooltips. Use the built-in TooltipContent or a custom one.
- Test. Check rendering with 1000+ tasks, measure LCP.
Timelines
| Gantt Type | Timeline |
|---|---|
| gantt-task-react with custom tooltip | 3–5 days |
| Custom SVG Gantt with drag-and-drop and dependencies | 2–3 weeks |
| Full-featured Gantt with resources and critical path | from 4 weeks |
Get a consultation for your project—we'll assess complexity and propose the optimal solution. Order a custom Gantt chart development and see: a custom component pays off by reducing approval time by 30%. Contact us for a detailed estimate of your project.