FastBid Sheet
image/vnd.fastbidsheet
Released Late 1990s
· by FastBid, Inc. (Scott Becker)
The image/vnd.fastbidsheet MIME type represents a proprietary image format used by FastBid, a legacy estimating and blueprint-viewing software for the construction industry. Today, this MIME type is most infamous in the developer community for causing widespread MIME-sniffing conflicts: standard web servers, MIME databases, and file parsers often misidentify modern Google FlatBuffers schema files (which also use the .fbs extension) as FastBid images, leading to unexpected errors in modern development pipelines and AI SDKs.
Technical Specifications
.fbs
Unknown
Magic Bytes & HTTP Headers
Unknown
Browser Support Matrix
| Browser | Status | Min Version |
|---|---|---|
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Not Supported | — |
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Not Supported | — |
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Not Supported | — |
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Not Supported | — |
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Not Supported | Legacy |
Advantages & Limitations
- Historically allowed the FastBid application to securely associate and load proprietary construction plans within its ecosystem
- Completely obsolete and unsupported in modern software environments
- The official IANA registration of the .fbs extension causes widespread false positives, breaking modern parsers, text editors, and AI SDKs attempting to read FlatBuffers schemas
Developer Code Snippets
File Detection Steps
How to programmatically detect a image/vnd.fastbidsheet
file by reading its raw bytes:
- 1 Due to its obscurity, file detection almost entirely relies on matching the .fbs extension to the IANA registry.
- 2 Developers working with FlatBuffers must actively bypass or override strict MIME detection for .fbs to prevent text files from being improperly base64-encoded or treated as binary FastBid images.
Software Support
Share & Embed
[](https://freewebptojpg.com/mime/image/fastbid)
<iframe src="https://freewebptojpg.com/mime/image/fastbid/embed" width="100%" height="280" style="border:1px solid #cbd5e1;border-radius:8px;" title="FastBid 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/fastbid.json
Open JSON
Frequently Asked Questions
Why is my FlatBuffers .fbs file being detected as an image?
The .fbs file extension is officially registered with IANA as image/vnd.fastbidsheet, a proprietary format for legacy FastBid construction software. Because standard MIME sniffers and operating system registries prioritize the official IANA database, they mistakenly identify your FlatBuffers schema text files as FastBid binary images.
What is a FastBid Sheet?
A FastBid Sheet is an obsolete proprietary format used by the FastBid construction estimating software to store digital blueprints, construction plans, and architectural layouts.
How do I fix the .fbs MIME type conflict in my application?
If your application processes FlatBuffers schemas, you must explicitly override your MIME detection library or web server configuration (like Nginx, Apache, or Python's mimetypes module) to map the .fbs extension to text/plain instead of relying on the default image/vnd.fastbidsheet fallback.