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Developer tools
HMAC Generator
Result
The result will appear here after you run the tool.
The result will appear here after you run the tool.
The result will appear here after you run the tool.
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About this tool
About this tool
HMAC Generator creates a keyed hash by combining a secret key with selected hash algorithm and message inside your browser. Output is shown as hex or base64 and remains local to your device.
Generate an HMAC from a message, secret key, and selected algorithm. Use the full-width workspace to generate output while reviewing syntax, encodings, protocol fields, and implementation details. The tool accepts plain text, provides focused options, and creates HASH output that you can inspect, copy, download, or save as a local draft.
Built for daily work
How to use this tool
How to use this tool
Configure the operation
Review Algorithm. The selected controls determine how the HMAC Generator interprets the source and builds the result.
Run the tool
Start the HMAC Generator and review the result, visual preview, and technical report. Correct any reported issue and run the tool again when necessary.
Export or continue the workflow
Copy or download the HASH result, save a browser-local draft, or open a related tool for the next conversion, validation, or cleanup step.
Key features
Key features
HMAC with SHA-1, SHA-256, SHA-384, or SHA-512
Provide a message and a secret key to compute a keyed-hash message authentication code using the selected SHA algorithm.
Separate key and message inputs
The secret key is entered in its own field so it is not mixed into the message text during editing or pasting.
Authentication code, not encryption
HMAC produces a verification tag. It does not encrypt the message and cannot hide the plaintext content.
Computed locally via SubtleCrypto
The Web Crypto API calculates the HMAC in the browser. Neither the message nor the secret key is sent to a server.
Practical use cases
Practical use cases
Private by default
For local tools, input is processed in your browser and is not sent to application analytics.
Data processing noticeTechnical details
Technical details
Input formatsplain text
Output formatsHASH
ProcessingLocal browser processing
Task controlsAlgorithm
Maximum local file25 MB per supported file
Workspace featuresFocus mode, examples, copy, download, local drafts, and result reports
Limitations and important notes
Limitations and important notes
- Review generated output before using it in production or security-sensitive workflows.
- Large or deeply structured input depends on available browser memory and may process more slowly on mobile devices.
- The tool implements practical browser-based processing and may not reproduce every feature of specialist desktop software or every vendor-specific extension.
- Keep the original source and review generated output before production, security-sensitive, financial, legal, or safety-critical use.
Frequently asked questions
Frequently asked questions
It creates a keyed hash by combining a secret key with a chosen hash algorithm and message inside your browser, outputting hex or base64.
It supports MD5, SHA-1, SHA-256, and SHA-512 as HMAC primitives as listed in the tool options.
No. Key and message are processed locally and not transmitted.
The tool accepts text keys in the current implementation; ensure encoding matches your verification system.
Related guides and solutions
Related guides and solutions
How to review HTTP security headers
A practical header-review checklist covering content restrictions, framing, MIME handling, transport, referrers, permissions, CORS, cookies, and caching.
Learn moreHow to inspect a JWT without confusing decoding with verification
A security-focused JWT inspection guide that separates readable payload data from signature verification and authorization decisions.
Learn moreWhat local browser processing means for online tools
A transparent explanation of local tool processing, temporary browser memory, local storage, downloads, analytics boundaries, and cases that require remote services.
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