01 · BUILD THE SCHEDULE
Build the schedule.
Turn the work into a real project plan - tasks, milestones, hierarchy, dates and duration - then shape the schedule directly on the Gantt.
Q3 Website Redesign
Alice
Jun - Sep
8 tasks
+ Add Task
Save Plan
Assignee: All
Collapse All
Dependencies: On
| # | Task | End |
|---|---|---|
| 1 | Discovery | 6 Jun |
| 2 | Interviews | 1 Jun |
| 3 | Requirements | 6 Jun |
| 4 | Design | 25 Jun |
| 5 | Wireframes | 14 Jun |
| 6 | Visual | 25 Jun |
| 7 | Development | 20 Aug |
| 8 | Launch ◆ | 21 Aug |
May 2026
June 2026
July 2026
Your plan. Your file. No login.
Dependencies · Critical path · Resource capacity · Baselines · MS Project compatible
READMESerious project scheduling, without heavyweight project management software. Build plans with dependencies, critical path, resource capacity and baselines, then keep them as files that are yours forever.
no cloud
no account
no subscription
Designed for laptop and desktop browsers
Everything you need. Nothing you don't.
Build real project schedules with automatic dependencies, task hierarchy, critical path, resource capacity and baselines, without adopting another project-management platform.
One HTML file. Your projects stay on your computer.
02 · CONNECT THE WORK
Connect the work.
Gantto supports real scheduling relationships, not just drawn bars. Set the dependency type that matches how the work actually happens, add lead or lag where you need it, and let the schedule respond automatically.
03 · UNDERSTAND THE SCHEDULE
Understand what drives the finish date.
Critical Path highlights the chain of dependencies and durations driving your planned finish.
Schedule Risk goes a step further - warning when a non-critical task's scheduled finish reaches or passes the end of the critical path.
Change the plan and both recalculate automatically.
SOLO · CRITICAL PATH + SCHEDULE RISK
04 · RESOURCE CAPACITY
Catch over-allocation before it catches you.
Add people to your resource pool, set their capacity and allocate them to tasks. Gantto warns when planned work exceeds available capacity so you can adjust the schedule.
05 · TRACK THE PLAN
Plans change. Keep sight of where you started.
Baselines capture the plan you agreed to, so you can see how far the current schedule has drifted. Track progress and status as work happens, log actual dates against planned ones, and step back through Plan History whenever you need to see what changed.
06 · OWN AND SHARE
Your project. Your files.
Plans stay as local files. Save, share or export them without a cloud project store to sign into.
JSON save / load
Standalone read-only HTML
PDF
PNG
CSV
One HTML file. Your projects stay on your computer.
Up and running, 30 seconds flat.
No sign-up flow. No "verify your email." No onboarding tour. The first thing you see is your plan.
T + 00s
Download the file.
Click Download Free. You get one file - gantto.html. No installer, no update channel, no auto-launch service.
T + 06s
Open it in your browser.
Double-click. It opens in Chrome, Safari, Firefox, Edge - any modern browser. No server. No internet connection required after this point.
T + 30s
Start planning.
Add tasks. Drag bars. Set dependencies. Save the plan as a .json file when you're happy. Commit it to git, mail it, drop it in Drive - your call.
One file. Two tiers.
Free forever, or pay once for Solo. No subscriptions, no renewal - that's the whole point.
TIER · FREE
£0/ forever
Everything you actually need to plan a project, right now.
- Full Gantt chart editor
- Task hierarchy & dependencies
- Milestones & sprint bands
- Assignee filtering & zoom levels
- Save & load JSON plans
- Share plans
- AI context export
- AI Prompt Helper & Paste from AI
- Status tracking - Not Started, In Progress, Blocked and more
- Import from MS Project - open a Project XML export, edit and save as Gantto JSON
- Dark, light & high-contrast themes
- Colour Themes - Default, Muted, Pastel & Grey Gantt bar palettes
- Custom date formats
- Basic print (Ctrl+P)
- Sprint management
RECOMMENDED
TIER · SOLO
£9.99/ once · forever
Pay once. Use it for the rest of your career. No expiry, no renewal.
- Everything in Free. No interruptions.
- All 8 premium templates included
- Grid View - a full-width, spreadsheet-style view of your plan with inline editing for every task field
- Share Read Only - export a standalone HTML file your team can open in any browser, no account or install needed, perfect for sharing with stakeholders
- PDF & PNG export
- CSV export
- Plan History - automatically keeps a rolling save history inside your plan file. Choose how many versions to retain in Settings, then revert to any previous save in one click
- Baselines
- Resource capacity & allocation - link assignees to a shared resource pool, set capacity, and get over-allocation warnings before they happen
- Critical Path Analysis
- Schedule Risk - flags any task whose actual dates run past your critical path's real finish, even though it isn't marked critical
More features coming for Solo users - you'll get them automatically.
Buy Solo - £9.99 →Gantto runs as a downloaded file in a laptop or desktop browser - not designed for phones or tablets.
TEMPLATES
Hit the ground running.
Don't start from a blank plan. Browse 8 ready-made templates - Wedding Planning, Product Launch, Software Sprint and more. Each one opens instantly in Gantto.
From £4.99.
Browse templates →VIDEO
See Gantto in action
See how to build and manage a project schedule, link tasks, identify the critical path and spot resource conflicts, without the complexity of traditional project management software.
Questions, answered plainly.
Q · 01
Does it really work with no internet?
Yes. Once gantto.html is on your disk you can pull the network cable, fly to Tokyo, retreat to a cabin in Vermont - Gantto keeps planning. The only thing that needs internet is downloading it.
Q · 02
How does the Solo licence work?
£9.99, once. You get a licence key to enter directly in the app. The reminder popup disappears permanently. Use it in any browser you own, forever - no internet check, validated entirely offline.
Q · 03
What browsers are supported?
Chrome, Safari, Firefox, Edge - anything shipped in the last three years. Brave, Arc, Vivaldi: also fine. Chrome and Edge have the best experience, supporting the native file-save dialog when exporting plans.
Q · 04
Does Gantto work on mobile?
Gantto is designed for desktop browsers. On iPhone and iPad, Safari can't open local HTML files - download and open Gantto on a Mac or PC for the best experience. We're exploring mobile support for a future version.
Q · 05
Can I share the file with my team?
The app file is just HTML - share it freely. For plans, save the .json and send it however you send files. Collaboration features are on the roadmap. For now, save the .json and send it - it works surprisingly well.
Q · 06
Can I import an existing MS Project file?
Yes. Export your plan from MS Project as XML, then import it into Gantto free, full edit and save included, no licence needed.
Q · 07
What happens to my data if I upgrade browsers?
Nothing, as long as you saved your plan as a .json file. The browser is just the viewer. The file is the truth.
Changelog
Recently shipped
v1.9.0
Oct 2026
- New Issues panel: broken dependencies, constraint conflicts, missed deadlines and what Gantto changed for you, in one place, with Reschedule, Remove broken link and Go to task.
- Undo now covers dragging and resizing bars, and changes to working days and holidays.
- Behaviour change: dependencies always schedule and the "Auto-sync dependencies" setting is gone. To keep a task where it is, set a constraint, or drag it later and Gantto holds it for you.
- Opening a plan never moves its dates. Tasks that start later than their dependencies need are held where they are, and broken links are listed instead of silently fixed.
- Only the link that is actually broken is drawn red, and holds Gantto added itself are marked separately from the constraints you set.
- Also in this release: Effort renamed to Duration, summary dependencies applied to each task, completed and started tasks no longer moved by others, PNG and PDF exports that follow your theme, and a range of scheduling fixes.
v1.8.3
Sep 2026
- The What's New window now shows every release in the current version series, newest first, instead of only the latest patch.
- Fixed Project XML import silently dropping notes, deadlines, actual dates, effort, constraints, calendar and resource assignments from the source file.
- Fixed an imported plan (from MS Project or a spreadsheet) inheriting settings from whatever plan was open beforehand.
- New plans now default to a Monday to Friday working week.
- Fixed Plan History's default save depth and corrected the Auto-save setting's description to match what it actually does.
- Fixed Effort going stale after a task's dates changed.
v1.8.2
Sep 2026
- Fixed an issue where Plan History could show or restore data from a different plan if multiple tabs were open at once.
v1.8.1
Sep 2026
- Fixed a bug where removing a constraint from a task with a "Finish-to-Finish" or "Start-to-Finish" dependency could leave it a couple of days off from where the dependency actually says it should be
- Fixed a bug where autosave-to-file wasn't stamping the plan version on disk, which could make a fully up-to-date file look outdated and trigger an unnecessary recheck the next time it was opened
- Fixed the What's New popup showing nothing (or just "Bug fixes.") instead of the last real release's details, for anyone on a bug-fix-only patch release
v1.8.0
Sep 2026
- Critical Path Analysis (Solo) - Dependency Map Insights now lists every distinct chain of tasks with zero scheduling slack, with a "Highlight Critical Path" toggle on the Network diagram, Gantt View, and Grid View
- Schedule Risk (Solo) - flags any task that isn't on the critical path but is currently dated to finish on or after the critical path's own finish date, right on the Gantt bar or Grid row
- Behaviour change: tasks with a dependency now always follow it, matching how Auto Scheduled tasks work in tools like MS Project. If a task's dates don't match its dependency exactly, they'll be corrected the next time the plan recalculates. If you need a task to hold a specific date on purpose, set a constraint (Must Start On, Start No Earlier Than, etc.) instead of just typing or dragging one - Gantto will now hold that date and flag it if it conflicts with the schedule
- Opening a plan saved by an older version of Gantto now corrects its dates immediately instead of asking first - a small dismissible notice appears only when a genuine dependency violation was corrected, with an optional detail view showing exactly what changed
- Must Start/Finish On and Start No Earlier/Finish No Later Than constraints now actually hold a task's dates, with a visible warning if a conflict arises
- Also in this release: Dependency Map Insights, Focus Mode, Project XML export, a WBS column, and a range of scheduling-integrity fixes
v1.7.0
Aug 2026
- Resource Capacity (Solo) - link assignees to a shared resource pool, set capacity, and get over-allocation warnings before they happen. Includes a per-task Allocation % field (edit panel, Grid View and Gantt task list columns), automatic assignee-to-pool linking, and full Undo support.
- Actual date dots on Gantt bars now sit at the bar's vertical centre with a connector line back to the bar edge, making it clear at a glance how far ahead or behind a task's actual dates are
- Fixed Share Read Only showing the Solo upgrade popup for Grid View instead of the plan - Grid View is now visible and fully populated for every recipient, locked the same way as Gantt and Late Tasks view
- Also in this release: native browser dialogs replaced with in-app confirmation windows throughout
v1.6.1
Aug 2026
- Persistent "Free" badge in the header for unlicensed users - click it to see what Solo unlocks. Never shown once a licence is active.
- Undo (Ctrl/Cmd+Z, toolbar button, and right-click menu) for task edits, indent/outdent, delete, and other plan changes made during the current session
- AI Prompt Helper now guides milestone creation when generating a plan
- Esc key now closes the task edit panel
- Grid View: double-click a task row to open the edit panel; Edit Task is also now available from the right-click menu in both Gantt and Grid views
- Removed "Copy Task List", consolidated into "Copy Plan for AI", now available from both the AI menu and Share menu
- Pasting a plan from AI now creates milestone tasks when explicitly marked as a milestone in the source text
- Day-level zoom now shows day-of-week headers and gridlines
- Task Ref now appears directly after Task Name in the edit panel, and its column heading and values are centred in both Gantt and Grid View
- Grid View: adding a subtask no longer opens the edit panel, consistent with adding a task
YOUR PLAN.
YOUR FILE.
YOUR SCHEDULE.
Serious project scheduling without the overhead.
No cloud · No account · No subscription
Gantto.app is an independent project built in the UK in 2026. Not affiliated with the original 2010 Gantto (YC S10, acquired 2013).
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