Last updated: 14 September 2026
Gantt Chart for Sheets (“the add-on”) is a Google Workspace add-on that turns a task list in a Google Sheets spreadsheet into a Gantt chart. By installing or using it you agree to these terms. If you do not agree, do not install it.
We grant you a personal, non-exclusive, non-transferable licence to use the add-on. You may not resell it, redistribute it, or attempt to extract or reuse its licence-key mechanism.
The add-on is free to use up to 50 tasks per chart, with no limit on project length.
Pro removes the task limit and unlocks dependency labels and custom chart colours. Pro is sold as an annual licence. When you buy it you receive a licence key by email.
Your key is issued to you. Sharing it publicly, or using one key across an organisation beyond the seats purchased, is a breach of these terms and we may invalidate the key.
Keys carry an expiry date and are checked on your own device; the add-on cannot contact us. A key keeps working for a short grace period after its expiry date so that a late renewal does not interrupt your work. If you lose a key, contact support with your order reference and we will reissue it.
If the add-on does not work for you, email us within 30 days of purchase and we will refund you in full. You do not have to give a reason.
The add-on cannot access the internet and does not transmit your spreadsheet contents anywhere. See the Privacy Policy for detail. You remain the owner of everything in your spreadsheets.
The add-on is provided “as is”. We do not warrant that it will be uninterrupted or error-free, or that the schedules it computes are correct for your purposes.
Check the output before relying on it. Scheduling software assists judgement; it does not replace it. Do not use this add-on as the sole basis for decisions where an error would cause financial loss, contractual breach, injury, or other serious harm.
To the fullest extent permitted by law, our total liability arising from your use of the add-on is limited to the amount you paid for it in the twelve months before the claim. We are not liable for indirect or consequential loss, including lost profits, lost data, or project delay.
Nothing here excludes liability that cannot lawfully be excluded.
The add-on runs on Google Apps Script inside Google Sheets. If Google changes or withdraws that platform, the add-on may stop working. We will refund the unused portion of a current annual licence if that happens and we cannot restore service.
You may stop using the add-on at any time by uninstalling it. We may suspend a licence key that is being used in breach of section 4, after telling you why.
If these terms change, the date above changes and the current version is published at this URL. Material changes will not apply retroactively to a licence you have already bought.
slowgrain.dev@gmail.com