Buy a license

The basic functionality of Simple Data Logger is available for free for personal, non-commercial use (see EULA). A Plus license enables the entire functionality of the software and allows commercial use. Click here to see the features only available with a Plus license.

Two-year Plus licenses

Please click on the button below to continue to our reseller FastSpring (your license and invoice will be created automatically).

*plus VAT or sales tax, where applicable. Click button to see prices in your local currency (if supported).

Your license will be valid for two years and includes all updates released during this period. After two years, the license will expire and you will need to purchase a new license to continue using the Plus features of the software (not a subscription, does not renew automatically).

90 days license

If you don’t need a perpetual license, click on the button below to purchase an SDL Plus license valid for 90 days (not a subscription, non-recurring):

*plus VAT or sales tax, where applicable. Click button to see price in your local currency (if supported).

Trial licenses

Please contact us if you would like to request a SDL Plus trial license before purchasing.

License FAQ

About FastSpring

Secure ordering by FastSpring

Based in California in the United States, FastSpring is our trusted reseller for digital products and your contractual partner for your purchase. FastSpring automatically generates your license keys and invoice immediately after your payment has been received.

Tax or VAT/GST

FastSpring calculates the VAT or sales tax that is due on your order and takes care of collecting and remitting the taxes. FastSpring’s W-9 form can be downloaded here (PDF).


If you have a valid European VAT ID, you can enter it during the purchase process and no VAT will be charged. If you forgot to do so, you can request a VAT refund by contacting FastSpring using this form.

Tax exempt (US)

If your organization is based in the US and tax exempt, you can either:

  1. Order first and then contact FastSpring using this form and upload your US tax exempt certificate to get a tax refund, or
  2. contact FastSpring before ordering so to they can create a custom tax-exempt order for you. Please refer to this page for further information (under “Set Up Tax-Exempt Order”).

Activating your license

Simply copy the license key to the license tab and click on apply:

Activating your license

Using one license on multiple devices

The EULA says that “one paid license is required for each device installation or instance of this software that you wish to use simultaneously”. This means that you can use a single license on multiple devices, provided that they are never used at the same time.

Example 1: You have 5 users working with SDL at the same time but those
users alternately use 10 computers (e.g. a desktop and laptop for each user). You would need to purchase only 5 licenses.

Example 2: There’s only one user, but there are 5 computers running SDL
simultaneously (e.g. to acquire data from multiple experiments). You’d
also need 5 licenses.

Example 3: One user is running two installations of SDL simultaneously on the same computer to acquire data from two connected scales. You’d need two licenses.

Buying licenses directly from us (Smartlux SARL)

We very much prefer that you buy your licenses through FastSpring’s fully automated process as described above. This frees up our time for further development of our software.

If you would still like to purchase licenses directly from us, please contact us. Please note that we charge a non-refundable fee of 40€ (excl. VAT) per order for manual order processing.

Becoming a reseller

Are you interested in selling our software to your customers? Click here to learn more and to apply for a reseller account.