LicenseGuard – License Key Verification & Activation API
LicenseGuard is a production-ready software licensing backend for developers who need secure license key validation, activation enforcement, and refund-based revocation without building custom infrastructure.
This API allows you to:
Validate license keys securely
Enforce per-device activation limits
Prevent key sharing
Automatically revoke access after refunds or cancellations
Track activation status in real time
Send a POST request to the /validate endpoint with:
licenseKey
deviceId
The API verifies the license, checks activation limits, and returns a clear validation response indicating whether the license is valid.
A lightweight /health endpoint is included for monitoring and uptime checks.
Indie developers selling downloadable software
SaaS tools distributed outside app stores
Game developers selling direct licenses
Plugin and theme creators
AI tool builders distributing desktop applications
Validates a license key and enforces per-device activation limits.
Validate License - Endpoint Features
| Object | Description |
|---|---|
Request Body |
[Required] Json |
{"valid":true}
curl --location --request POST 'https://zylalabs.com/api/11900/license+verification+and+activation+api/22616/validate+license' --header 'Authorization: Bearer YOUR_API_KEY'
--data-raw '{
"licenseKey": "TEST-LICENSE-123",
"deviceId": "device-abc-001"
}'
| Header | Description |
|---|---|
Authorization
|
[Required] Should be Bearer access_key. See "Your API Access Key" above when you are subscribed. |
No long-term commitment. Upgrade, downgrade, or cancel anytime. Free Trial includes up to 50 requests.
LicenseGuard prevents license key sharing, enforces per-device activation limits, and automatically revokes access after refunds — without you building your own licensing backend.
Call the /validate endpoint with a license key and device ID from your app. You’ll receive a clear JSON response indicating whether the license is valid.
Yes. It’s ideal for desktop software, plugins, games, and downloadable tools distributed outside app stores.
Yes. You can restrict how many devices a license can activate.
Access can be revoked automatically depending on your configuration.
Yes. Zyla provides a 7-day free trial so you can test integration before committing.
It’s primarily designed for license-key based products. For SaaS subscription management, additional logic may be required.
Yes. LicenseGuard runs on a scalable hosted backend and is designed for real-world production usage.
The /validate endpoint returns a JSON response indicating the validity of the license key. It includes a boolean field "valid" that specifies whether the license is active and meets activation limits.
The primary field in the response from the /validate endpoint is "valid," which is a boolean indicating if the license key is valid. Additional fields may be included in future updates for more detailed responses.
The response data from the /validate endpoint is structured in JSON format. It typically contains key-value pairs, making it easy to parse and integrate into applications.
The /validate endpoint accepts two parameters: "licenseKey" (the key to validate) and "deviceId" (the unique identifier for the device attempting activation).
Users can customize requests to the /validate endpoint by providing different "licenseKey" and "deviceId" values to check the validity of specific licenses on various devices.
Typical use cases include validating software licenses during installation, enforcing activation limits for plugins, and managing access for SaaS applications based on license status.
Data accuracy is maintained through secure validation processes and real-time checks against the licensing database, ensuring that only valid licenses are activated.
If the /validate endpoint returns an empty or partial result, it typically indicates an invalid license or an unregistered device. Users should implement error handling to manage these scenarios effectively.
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To give you the opportunity to experience our APIs without any commitment, we offer a 7-day free trial that allows you to make up to 50 API calls at no cost. This trial can be used only once, so we recommend applying it to the API that interests you the most. While most of our APIs offer a free trial, some may not. The trial concludes after 7 days or once you've made 50 requests, whichever occurs first. If you reach the 50 request limit during the trial, you will need to "Start Your Paid Plan" to continue making requests. You can find the "Start Your Paid Plan" button in your profile under Subscription -> Choose the API you are subscribed to -> Pricing tab. Alternatively, if you don't cancel your subscription before the 7th day, your free trial will end, and your plan will automatically be billed, granting you access to all the API calls specified in your plan. Please keep this in mind to avoid unwanted charges.
After 7 days, you will be charged the full amount for the plan you were subscribed to during the trial. Therefore, it's important to cancel before the trial period ends. Refund requests for forgetting to cancel on time are not accepted.
When you subscribe to an API free trial, you can make up to 50 API calls. If you wish to make additional API calls beyond this limit, the API will prompt you to perform an "Start Your Paid Plan." You can find the "Start Your Paid Plan" button in your profile under Subscription -> Choose the API you are subscribed to -> Pricing tab.
Payout Orders are processed between the 20th and the 30th of each month. If you submit your request before the 20th, your payment will be processed within this timeframe.
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