BlockFact Image
image/vnd.blockfact.facti
Released 2025
· by BlockFact
The image/vnd.blockfact.facti MIME type represents the BlockFact image format, a cryptographic media container designed to guarantee the authenticity of digital photography. It encapsulates standard image payloads alongside zero-knowledge proofs (Groth16), invisible watermarking, and Poseidon hashes registered on the StarkNet blockchain. This creates an immutable chain of custody, enabling journalists, creators, and legal professionals to definitively prove when, where, and by whom a photo was captured, while combating AI-generated deepfakes.
Technical Specifications
.facti
None (Pass-through to embedded payload)
Magic Bytes & HTTP Headers
Unknown
Browser Support Matrix
| Browser | Status | Min Version |
|---|---|---|
|
|
Not Supported | — |
|
|
Not Supported | — |
|
|
Not Supported | — |
|
|
Not Supported | — |
|
|
Not Supported | Legacy |
Advantages & Limitations
- Provides undeniable, mathematically verifiable proof of a photo's origin (time, location, and device) via the StarkNet blockchain [1.3.1]
- Privacy-first design utilizes zero-knowledge proofs (Groth16), meaning the actual image is never uploaded to a central server or blockchain
- Invisible watermarking ensures that even if the image is screenshotted or cropped, tampering can be detected
- Lacks native rendering support in web browsers and standard image viewers, requiring specialized software to view
- Requires blockchain registration at the moment of capture, making it incompatible with existing legacy photos
- The proprietary nature of the container limits integration to environments supporting the BlockFact SDK
Developer Code Snippets
File Detection Steps
How to programmatically detect a image/vnd.blockfact.facti
file by reading its raw bytes:
- 1 Due to its novelty, standard magic file databases do not recognize .facti files natively.
- 2 Verification and extraction of the payload should be handled using the official @blockfact/react-native-facti-pro SDK.
Software Support
Conversion Tools
Share & Embed
[](https://freewebptojpg.com/mime/image/facti)
<iframe src="https://freewebptojpg.com/mime/image/facti/embed" width="100%" height="280" style="border:1px solid #cbd5e1;border-radius:8px;" title="FACTI Specs"></iframe>
JSON API
All data on this page is available as a free, open JSON API. Use it in your project, documentation, or tooling.
GET https://freewebptojpg.com/mime/image/facti.json
Open JSON
Frequently Asked Questions
What is a .facti file?
A .facti file is a specialized image container created by the BlockFact platform. It holds the original image data, an invisible watermark, and cryptographic proofs that are registered on the StarkNet blockchain to verify the photo's authenticity [1.1.1].
Does BlockFact upload my photos to the blockchain?
No. By design, your photos never leave your device. The BlockFact app generates a mathematical zero-knowledge proof and a cryptographic hash locally, and only this tiny proof is registered on the blockchain.
Can web browsers open .facti files?
No modern web browsers natively support rendering .facti files. Viewing the image and verifying its blockchain provenance requires the BlockFact web viewer, their mobile app, or integrating their official React Native SDK.