Licence and refund terms

Last updated 5 November 2026

These terms cover Calamo Pro, the desktop app and command-line tool. The browser tool on this site is free and needs no purchase. Your files are never uploaded by either of them.

In short

  • You buy Calamo Pro from Polar, our reseller. Polar takes the payment and charges VAT or sales tax.
  • We, Michal Piják DEV, give you the licence to use the software.
  • One licence is for one person, on up to 3 computers. You pay once.
  • Try it free for 14 days first. After you buy, you can ask for a full refund within 30 days of purchase, for any reason.
  • The app sends nothing but the licence check. No files, file names, column names or values.

Who sells and who licenses

Calamo Pro is sold by Polar Software, Inc., 3500 South DuPont Highway, Dover, DE 19901, USA, as merchant of record. Your purchase contract and payment are with Polar under the Polar Buyer Terms. Polar sends the receipt and the invoice and handles payment questions.

The software is made and licensed by Michal Piják DEV, Slovakia (details under Who runs Calamo). The licence on this page is between you and us. Polar’s Buyer Terms say that the licence terms of the maker apply to the software, and that is this page.

What you get

  • A licence for one person to use Calamo Pro, the desktop app and the command-line tool, for personal or work use.
  • The licence key arrives from Polar by email. You can activate it on up to 3 computers at a time. To move it to another computer, remove it first (in the app, with calamo license --remove, or in Polar’s customer portal, linked in your purchase email).
  • You can use the version you bought for as long as you like. There is no subscription and no expiry.
  • Updates within version 1 (1.0, 1.1, 1.2 and so on) are included. For at least 2 years from your purchase we provide free updates, including security fixes, needed to keep the version you bought working as described, and we tell you about them by email.
  • If we ever stop selling Calamo Pro or stop using Polar, we will release a version that works without the licence check.
  • Windows, Linux and macOS are supported. The macOS version is new (beta): if it does not work on your Mac, the 30-day refund applies as for any other reason.

A licence for a team means one licence per person who uses Calamo Pro.

Free trial

Calamo Pro works fully for 14 days from the first start, without a key and without an account. The trial is counted on your computer; nothing is sent. After 14 days, the app asks for a licence key.

Price and payment

The price is shown on the pricing page and again at checkout, with the tax for your country: in the EU, the UK and most other countries VAT is included in the price; in the US, Canada and India sales tax is added where it applies. You pay once. Polar accepts the payment methods shown at checkout.

Refunds

  • 30 days, any reason. Within 30 days of buying, you can ask for a full refund. You don’t have to give a reason.
  • How to ask. Email hello@calamo.io. It helps if you write from the address you used to buy or add your order number. The money goes back through Polar to your original payment method within 14 days of your request.
  • After a refund the licence key is revoked. The app forgets the key at its next licence check and asks for a key again.

Right of withdrawal in the EU

If you are a consumer in the EU, you can withdraw from the purchase within 14 days of buying, without giving a reason. Our 30-day refund above already covers this: just email us within 30 days, and you get the full price back within 14 days. You keep the 30-day refund even if the checkout asked you to agree that the download starts at once.

If something does not work

Tell us at hello@calamo.io, with what you did and what happened. Polar, as the seller, leaves support for the software to us, so we handle every report. We confirm it, tell you by when we will fix it and fix a fault within 30 days, unless there is an objective reason we cannot control. If we cannot fix it, you get the price back within 14 days. If we think it is not a fault, we tell you why in writing.

If you are a consumer, you have the legal rights for faulty digital content (in Slovakia, § 852a to § 852n of the Civil Code) for two years from delivery. They are rights against the seller, Polar, and we handle them for it. Nothing on this page limits them.

Calamo Pro gives the same answer for the same files, but it is still a tool. Check results that matter before you act on them, and keep copies of important files. Calamo changes a file only when you save it.

What the app sends

Calamo Pro reads your files on your computer and never uploads them. The only thing Calamo itself sends over the internet is the licence check, to Polar (api.polar.sh):

  • when you enter a key: the key, our Polar organisation ID and the label “Calamo Pro”, then a first check with the ID of this activation;
  • about every 30 days, when the computer is online: the key and the ID of this activation, to confirm the key is still valid;
  • when you remove the key: the same, to free the activation.

Polar sees your IP address with these requests, as any server does. If the check cannot reach Polar, for example offline or behind a firewall, the app keeps working. Only an answer from Polar that the key is revoked, unknown or invalid stops it. More in the privacy policy.

What you may not do

  • Share your key with other people, or use one licence for more than one person.
  • Sell, rent or lend the software or the key.
  • Get around the licence check or the trial.
  • Reverse-engineer the software, except where the law allows it.

Calamo is our work and we keep all rights to it. The licence gives you the right to use it as described here, nothing more. If you break these rules, we can revoke the key after telling you why by email.

Liability

We are responsible for Calamo Pro as the law of Slovakia provides. Nothing on this page limits your rights as a consumer, or our liability for harm we cause on purpose or by gross negligence.

Changes to these terms

We may update this page, for example when macOS support or new features arrive. A change never takes away what you already bought: the licence for the version you bought stays as it was when you bought it. The date at the top shows the last change.

Law and disputes

These licence terms are governed by Slovak law. If you are a consumer living in another country, you keep the protection that the law of your country gives you and cannot be waived, and you can go to the courts there. The purchase contract with Polar is governed by the Polar Buyer Terms, which also do not take away the consumer rights of your country.

These terms are in English, and at checkout you confirm that you agree to them in English. If you would like them in another language, write to us and we send you a translation; the English text stays the one that applies.

If you disagree with how we handled a complaint, write to us first at hello@calamo.io. If you are a consumer living in the EU and we reject your request about the licence or our support, or do not answer within 30 days, you can turn to the alternative dispute resolution body, the Slovak Trade Inspection (SOI), at ars@soi.sk (how it works), or to another body on the list kept by the Slovak Ministry of Economy.

Who runs Calamo

  • Michal Piják DEV, sole trader
  • Place of business: Na Hrebienku 1498/35, 811 02 Bratislava, Slovakia
  • Home address: Hálova 2, 851 01 Bratislava, Slovakia
  • Company ID (IČO): 57396655
  • Registered in the trade register of the District Office Bratislava (Okresný úrad Bratislava), no. 110-362285
  • Email: hello@calamo.io (also for security issues in Calamo)
  • Phone: +421 944 477 947
  • Not a VAT payer. Polar charges and pays the VAT on every sale.
  • Supervisory authority: Slovak Trade Inspection (SOI), Inspectorate for the Bratislava Region, Bajkalská 21/A, P. O. BOX 5, 820 07 Bratislava, Slovakia

How we handle personal data: privacy policy.