Datovka Lhůty
Every message in your official mailbox has a deadline. The extension finds it, adds it to your calendar, and reminds you before the deemed delivery period starts running.
Finanční úřad pro Středočeský kraj · Výzva k doplnění
do 15 dnů od doručení
- Lhůta
- 6. 10. 2026 (Monday)
- Doručeno
- 21. 9. 2026 · read
- Co chtějí
- supplement a VAT attachment for 8/2026
- Reminder
- 3 Oct in Chrome
This is what an extension card looks like above the page you're working on. A demo, not real data.
What are you doing manually today
Every company and sole trader is legally required to have an official mailbox. A message is deemed delivered after 10 days, even if you haven't opened it, and from that moment, deadlines start running for appeals, supplements, or payment. Official letters are long, the deadline is hidden somewhere on the third page, and no one will remind you.
What the extension can do
- Short summary of every message on datovka.gov.cz: who is writing, what they want, by when.
- Finding the deadline in the text (e.g. "within 15 days of delivery") and calculating the exact date based on the delivery date.
- Add the date to your calendar (Google, Apple, Outlook) with a single click.
- Chrome reminder 3 days before the deadline and 2 days before the deemed delivery of unread messages.
- Save the message as a PDF, including the delivery receipt, to a folder of your choice.
- Overview of all active deadlines in one place, sorted by what is most urgent.
- For accountants: switch between client mailboxes and view all deadlines in one shared overview.
How it looks
- 1
Open the message
On datovka.gov.cz as usual.
- 2
You see the deadline
Found in the text and calculated to a date.
- 3
Add to calendar
One click. Chrome reminds you by itself.
Price
Free
CZK 0
Message summary and deadline detection are free. The extension adds calendar entries, reminders, and an archive.
Pro
CZK 99 monthly, excluding VAT
All the features above. Cancel anytime, invoices are automatic. Those who reach out before launch get the first month free.
Privacy and security
The extension works only in your browser, on the data box you are logged into. We do not send the content of messages to our servers. Summaries are created directly in Chrome (Chrome's built-in AI) or through your own AI key if you enter one. Reminders and the deadline overview stay in your Chrome; nothing reaches us.
Frequently asked questions
Do you see the content of my messages?
No. Messages, deadlines and reminders stay in your browser; nothing reaches us.
Does it work with Datovka, the app by CZ.NIC?
Datovka is a desktop program. Our extension works with the web mailbox on datovka.gov.cz, which most people use.
What if it doesn't find the deadline?
It will tell you. It never guesses. You can enter it manually and the reminder works just the same.
When can I start using it?
We are still building it. Interest decides the order — leave your e-mail and tell us you want this one. You get a message on release day and the first month of Pro free.
I want Datovka Lhůty
Leave your email and get the extension on launch day, first month free. In the note, tell us what takes you the most time today — we'll build it around that.