Diagramium

Overview

Diagramium is a browser-based Gantt chart maker for building project schedules and presenting them step by step. It suits people who need a lightweight way to map tasks and dependencies without creating an account. Its free access and account-free exports are strong advantages, but charts live in browser storage, so export anything you cannot afford to lose.

Key features

Schedules can include tasks, dependencies, milestones, progress, a highlighted critical path, and a Today marker. Calendar dates or project days let teams choose whether to anchor a plan to real dates or track work relative to its start; Daily, Weekly, and Monthly scales cover different planning horizons. This is a focused scheduling toolkit rather than a broad project-management suite.

Present mode reveals tasks step by step, with optional AI voice narration, subtitles, and speaker notes for each step. That makes the chart usable as a structured walkthrough for a class or project update, not just a static schedule.

The editor works offline after it has loaded, and the maker says charts remain on the device and in exported files. PNG, SVG, and PDF exports are available without an account; animated GIF, video, and animated SVG require a free Google-sign-in account. That split is practical for static sharing, though users wanting animation must accept the sign-in step.

Privacy protections include no diagram-content upload, no cookies, and no third-party analytics. The policy does describe anonymous gallery engagement counts and export-format totals. Charts are saved in browser storage, however, and clearing site data can permanently erase diagrams that have not been exported. Account creation is optional; it uses Google sign-in through Supabase, and the policy says Diagramium neither sees nor stores a Diagramium password.

Pricing

Both plans cost nothing. Guest needs no account and includes chart building, presentations, and PNG or PDF export. It is the simplest fit for occasional scheduling and static output, but does not include the animated export formats.

Free account also costs nothing, with no payment, and adds animated GIF, video, and animated SVG exports. It is the better choice when a presentation needs motion; the trade-off is signing in with Google. There is no paid tier described here.

Platforms

Diagramium runs on the web. The browser editor can continue working offline once loaded, but charts are stored in browser storage, making export important for backup and transfer.

Who it's for

The maker names developers, product managers, teachers, analysts, and support teams as intended users. It is especially suited to individuals or groups sharing a schedule as an exported image, PDF, or narrated step-by-step presentation. It is less suitable for anyone who needs durable cloud storage or expects a full project-management workspace.

Pros and cons

• Pros: No-account chart creation and PNG or PDF export keep the basic workflow accessible.
• Pros: Dependencies, milestones, progress, and critical-path highlighting support more informative schedules than a simple task list.
• Pros: Stepwise presentation with narration, subtitles, and speaker notes can turn a schedule into a guided briefing.
• Cons: Unexported charts can be lost when browser site data is cleared, so local storage is a real backup risk.
• Cons: Animated exports require Google sign-in, unlike the static formats.
• Cons: The web-only platform may not suit people seeking a native desktop or mobile app.

Alternatives

For broader customer-journey mapping choices, browse Customer Journey Mapping Software; for more Gantt-focused options, see Gantt Chart Software.

CX Impact is worth considering if you want a free, MIT-licensed project whose code is available across Linux, macOS, web, and Windows; AI agent and model usage depends on your plan. Milkymap offers journey-mapping tools on iOS and web, with a free single-user basic plan and a €9 a month single-user Pro plan for consultants.

Custellence is a web option for journey maps: its free plan caps use at one workspace, two users, and two maps, while its $199 a month Collaborate plan removes those limits. Customer Journey App has a free web plan for one user and three journey maps, with manual mapping, templates, several export formats, and ten version snapshots.

Funnelytics may fit Shopify users who want a free app with read-only store access, or teams considering its $39 a month Map Pro plan. IteroJM offers a free web plan capped at one journey map, persona, metric, and manager seat. JourneyIQ provides a free starter plan for one journey and five stages, including three AI scans per month. JourneyTrack has a 30-day free basic period with three journeys, one workspace, three editors, and unlimited viewers.

Verdict

Choose Diagramium if you need a free, browser-based Gantt chart maker with task dependencies, clear exports, and a presentation mode that can guide an audience through the plan. Its chief drawback is the dependence on browser storage: export charts you need to keep. Look elsewhere if persistent shared storage, a native app, or a broader project-management system matters more than account-free scheduling.