Privacy Policy
Effective Date: October 29, 2026
Last Updated: October 30, 2026
1. Introduction
Welcome to CarbonSutra (https://carbonsutra.com), a carbon emission estimation platform operated by Contactous ("Company", "we", "our", or "us"), a registered entity in Singapore.
We respect your privacy and are committed to protecting your personal information. This Privacy Policy explains what information we collect, how we use it, how it is shared, and how it is retained when you use CarbonSutra APIs, tools, website, and Google Workspace Add-on.
2. Information We Collect
CarbonSutra provides services through three access channels.
2.1 Third-Party API Marketplaces and External Portals
When you access CarbonSutra APIs through third-party marketplaces or developer platforms, such as RapidAPI, Postman Public Workspace, API.Market, or ZYLA:
- Authentication information: We process API keys, authorization tokens, and authentication headers required to validate API requests.
- Calculation information: We process the operational parameters submitted with API requests to perform carbon emission calculations.
- Third-party account information: Account registration and profile information collected by these platforms are governed by their respective privacy policies.
2.2 CarbonSutra Google Workspace Add-on
When you install and authorize the CarbonSutra Google Sheets Add-on, we may access and process the following information, depending on the features you use:
- Google account information: Your Google email address and profile information, where requested and made available by the authorization process, for account identification and API key management.
- Spreadsheet information: Values from spreadsheet cells that you select or that are required by the emission estimation workflow.
- Calculation inputs: Data entered or stored in your spreadsheet that is necessary to perform the requested carbon emission calculations.
- API configuration: Your CarbonSutra API key and related user-specific configuration used to authenticate requests.
Purpose of access: Spreadsheet information is accessed to process your requested emission estimation calculations and return calculated results, including CO₂-equivalent values and explanatory information, to your spreadsheet.
API transmission: The calculation inputs required for the requested operation are transmitted to the CarbonSutra API at:
https://api.carbonsutra.com/api/v1/sefr_estimation
The API processes those inputs and returns calculation results to the add-on. Your spreadsheet data is not used for advertising or unrelated purposes.
2.3 CarbonSutra API Playground
When you use the API Playground at https://carbonsutra.com/api-playground:
- Information collected: Your email address and the API request parameters you submit.
- Purpose: Your email address is used to generate and deliver an authorization code or API key. Request parameters are processed to execute the API operations you initiate.
3. How We Use Your Information
We use collected information only for legitimate service operations, including:
- Generating, delivering, validating, and managing API keys and authentication tokens.
- Identifying and authenticating users across CarbonSutra services.
- Processing carbon emission estimation requests and returning calculation results.
- Applying service usage limits and managing API access.
- Maintaining service reliability, security, and operational performance.
- Responding to support requests and communicating important technical or security notices.
We do not use Google user data or spreadsheet contents for advertising, advertising profiling, or unrelated marketing purposes.
4. Google API Services User Data and Limited Use
CarbonSutra's use and transfer of information received from Google APIs complies with the Google API Services User Data Policy, including its Limited Use requirements:
https://developers.google.com/terms/api-services/user-data-policy
Specifically:
- Limited purpose: Google user data is accessed and used only to provide the Google Workspace Add-on features that you request, including spreadsheet-based emission calculations and API key management.
- Calculation processing: Spreadsheet values required for a calculation are transmitted to the CarbonSutra API operated by Contactous to process your request and return results.
- No advertising: Google user data is not used for advertising, advertising profiling, or targeted advertising.
- No AI model training: Google user data is not used to train, retrain, or improve generalized artificial intelligence or machine learning models.
- No unauthorized disclosure: Google user data is not sold or disclosed to third parties except as necessary to provide the requested service, comply with applicable law, or as otherwise permitted by the Google API Services User Data Policy.
- Human access: Access to Google user data is restricted to authorized personnel when necessary for security, support, troubleshooting, or compliance purposes.
5. Information Sharing and Disclosure
We do not sell or rent personal information or Google user data.
Information may be processed or disclosed in the following limited circumstances:
- CarbonSutra API processing: Spreadsheet calculation inputs and required authentication information are sent to the CarbonSutra API operated by Contactous to perform the calculations requested by the user.
- Service providers: Infrastructure, hosting, and operational service providers may process information on our behalf where necessary to operate and secure CarbonSutra services.
- Legal requirements: Information may be disclosed where required by applicable law, legal process, court order, or valid governmental request.
- Security: Information may be processed when necessary to investigate or prevent fraud, abuse, security incidents, or unauthorized access.
We do not permit service providers to use Google user data for advertising or unrelated purposes.
6. Data Security
We implement administrative and technical safeguards designed to protect information against unauthorized access, loss, misuse, alteration, or disclosure.
These measures include:
- HTTPS and TLS encryption for data transmitted between users, CarbonSutra services, and the API.
- Authentication controls for API access.
- Restricted access to systems and information based on operational requirements.
- User-specific storage for API configuration within the Google Apps Script environment.
- Security monitoring and measures intended to identify unauthorized access or misuse.
No method of transmission or electronic storage is completely secure. We continuously review our safeguards to maintain appropriate protection for the information we process.
7. Data Retention and Deletion
We retain information only for as long as necessary to provide our services, meet operational requirements, resolve disputes, and comply with applicable legal obligations.
- Spreadsheet information: Calculation inputs are processed to fulfil the requested operation. The calculation results are returned to your spreadsheet. Spreadsheet contents remain subject to your Google account and spreadsheet retention settings.
- API keys and account information: Account information and API keys are retained while needed to provide the service, subject to applicable inactivity and account deletion policies.
- Calculation records and logs: Operational logs and request records may be retained for service reliability, security, troubleshooting, and auditing. Where possible, these records are minimized or anonymized.
- Deletion requests: You may request deletion of personal information and associated API account records by contacting us. We aim to process eligible deletion requests within 30 days, subject to legal and legitimate operational retention requirements.
Deleting information held by CarbonSutra does not automatically delete information stored in your Google Sheets. You remain responsible for deleting spreadsheet contents from your Google account.
8. Your Privacy Rights
Depending on your location and applicable privacy laws, including the EU GDPR, UK GDPR, and Singapore PDPA, you may have the right to:
- Access: Request information about the personal data we hold about you.
- Correction: Request correction of inaccurate or incomplete personal information.
- Deletion: Request deletion of your personal information and associated API account records.
- Withdrawal: Stop using the Google Workspace Add-on and revoke its Google account permissions through your Google Account settings.
To exercise these rights, contact us at:
Email: support@carbonsutra.com
We will review and respond to your request in accordance with applicable legal requirements.
9. Children's Privacy
CarbonSutra is not intended for children under the age required to independently consent to data processing under applicable law. We do not knowingly collect personal information from children in violation of applicable privacy requirements.
10. Changes to This Privacy Policy
We may update this Privacy Policy to reflect changes to our services, data practices, or legal and platform requirements.
Any updates will be published on this page with a revised "Last Updated" date. We encourage users to review this page periodically.
11. Contact Us
If you have questions, concerns, or requests regarding this Privacy Policy or our data practices, contact us:
CarbonSutra (a division of Contactous)
Website: https://carbonsutra.com
Email: support@carbonsutra.com
Location: Singapore