Hash Calculator — MD5, SHA-1, SHA-256, SHA-384, SHA-512 Online
Calculate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes for any text or file. Supports HMAC with secret keys, batch file hashing, and multiple output formats (hex, uppercase, base64). Verify hashes against expected values instantly. 100% client-side — nothing is sent to any server.
How to Use the Hash Calculator
- Type or paste text in the input area — hashes are calculated in real-time as you type.
- Switch to the File tab to hash one or more files. Drag-drop or click to browse.
- Toggle HMAC and enter a secret key to compute keyed hashes for message authentication.
- Choose an output format — lowercase hex (default), uppercase hex, or base64 encoding.
- Paste an expected hash in the Compare field to verify your input matches — green checkmark means match, red X means mismatch.
- Click the copy icon next to any hash to copy it to your clipboard instantly.
Hash Algorithms Explained
MD5 (128-bit) is fast but cryptographically broken — collisions have been found. Use it only for checksums, not security.
SHA-1 (160-bit) was deprecated for TLS certificates in 2017 after the SHAttered attack. Still used for Git commit identifiers.
SHA-256 / SHA-384 / SHA-512 belong to the SHA-2 family — the current standard for digital signatures, certificate chains, and blockchain. SHA-256 is the most widely used.
HMAC adds a secret key to any hash algorithm, turning it into a message authentication code. HMAC-SHA256 is commonly used for API request signing and webhook verification.
Frequently Asked Questions
MD5 is still widely used for non-security purposes: file download checksums, duplicate detection, cache keys, and database partitioning. This tool includes it so you can verify existing MD5 hashes — just don't use it for password storage, digital signatures, or any security-sensitive application.
For most modern applications, use SHA-256. It's fast, secure, and universally supported. For higher security requirements (long-term data integrity), use SHA-384 or SHA-512. Use HMAC-SHA256 if you need to verify both integrity and authenticity with a shared secret.
HMAC (Hash-based Message Authentication Code) combines your message with a secret key before hashing. This produces a tag that only someone with the same key can generate. It's used for API authentication (e.g., Stripe webhook signatures), JWT tokens, and verifying data hasn't been tampered with in transit.
No. All hashing happens in your browser using the Web Crypto API and a pure-JavaScript MD5 implementation. File contents never leave your device — the tool reads them locally via the File API and processes them entirely on the client side.
Hex encoding represents each byte as two hexadecimal characters (0-9, a-f). It's human-readable, case-insensitive for comparison, and the most common format for displaying hashes. Base64 encoding represents bytes using A-Z, a-z, 0-9, +, and /. It's more compact (33% smaller than hex) and commonly used in JWTs, PEM certificates, and binary data transport.
Yes. Select multiple files in the file browser or drag several files onto the drop zone. Each file gets its own set of hash results displayed separately, along with file metadata (name, size, type). All files are processed in parallel for speed.
Use Cases
Verifying File Integrity After Download
Compare the hash of a downloaded file with the expected value to ensure it wasn't corrupted or tampered with during transfer.
Generating Password Hashes
Create secure password hashes using SHA-256 or other algorithms for storing credentials safely in databases.
Checking Data Checksums
Generate checksums for data files to verify data integrity during storage or transmission between systems.
Creating Digital Signatures
Use HMAC with secret keys to create message authentication codes for verifying data authenticity and integrity.
Validating Blockchain Transaction Hashes
Verify SHA-256 hashes used in blockchain transactions and cryptocurrency addresses for validation purposes.