TOOL CATEGORY

Free Online Cryptography Tools

Generate passwords, inspect tokens, calculate hashes, study classical ciphers, and use modern or legacy encryption tools with private browser processing and explicit security limits.

Updated July 24, 2026

Search cryptography tools

33 of 33 tools shown

Passwords & Authentication

Generate, estimate, derive, and inspect authentication secrets without sending them to a server.

4 tools

CalculatorSecure Password GeneratorCreate cryptographically random passwords with adjustable length and character sets, then copy the result without uploading it.Open tool CalculatorTOTP Code GeneratorGenerate a six- or eight-digit time-based one-time password from a Base32 secret with a visible refresh countdown.Open tool CalculatorDeterministic Password GeneratorDerive a repeatable site-specific password from a private master phrase, service label, counter, and output length.Open tool CalculatorPassword Strength CheckerEstimate password guess resistance, detect common patterns, and show practical improvement feedback without transmitting the password.Open tool

Modern Encryption & Signatures

Use modern browser cryptography and clearly scoped regional standards for encryption, keys, signatures, and verification.

4 tools

CalculatorRSA Encryption & SignaturesGenerate RSA keys, encrypt short messages with OAEP, sign with PSS, and verify signatures using modern SHA-256 defaults.Open tool CalculatorSM2 Encryption & SignaturesGenerate SM2 key pairs, encrypt and decrypt text, sign messages, and verify signatures with explicit encoding choices.Open tool CalculatorSM4 Encryption ToolEncrypt or decrypt text with a 128-bit SM4 key using ECB or CBC compatibility modes and Hex or Base64 output.Open tool CalculatorAES Encryption ToolEncrypt text with AES-256-GCM and a password-derived key, or decrypt a versioned envelope containing its salt, IV, and ciphertext.Open tool

Classical Ciphers

Study reversible historical ciphers with transparent alphabets, keys, and intermediate rules.

5 tools

CalculatorROT Cipher ToolTransform letters, digits, or both with ROT13, ROT5, and ROT18 while preserving punctuation and letter case.Open tool CalculatorCaesar Cipher ToolShift Latin letters by any value, reverse the shift, or display all 26 candidates for manual brute-force analysis.Open tool CalculatorHill Cipher ToolEncrypt or decrypt A–Z text with an invertible 2×2 matrix and inspect validation for keys that have no modular inverse.Open tool CalculatorRail Fence Cipher ToolWrite text across two to eight zigzag rails, reconstruct the path, and reverse the transposition without changing characters.Open tool CalculatorVigenère Cipher ToolApply a repeating alphabetic keyword to encrypt or decrypt Latin text while preserving punctuation and original case.Open tool

Hashes, MACs & Checksums

Create deterministic digests, keyed authentication codes, and compatibility checksums with the right terminology.

7 tools

CalculatorSHA Hash GeneratorGenerate SHA-1, SHA-256, SHA-384, or SHA-512 digests from text and view the output as lowercase Hex or Base64.Open tool CalculatorMD5 Checksum GeneratorCalculate uppercase or lowercase MD5 digests for compatibility checks while keeping the algorithm’s security limits visible.Open tool CalculatorSHAKE Hash GeneratorCreate variable-length SHAKE128 or SHAKE256 extendable-output hashes and choose the exact byte length of the result.Open tool CalculatorKeccak Hash GeneratorGenerate Keccak-256 or Keccak-512 digests for Ethereum and pre-standard SHA-3 compatibility without confusing the two paddings.Open tool CalculatorHMAC Generator & VerifierCreate or verify an HMAC-SHA-256, HMAC-SHA-384, or HMAC-SHA-512 value from a message and shared secret.Open tool CalculatorCRC-32 CalculatorCalculate the standard CRC-32 value of UTF-8 text as hexadecimal and unsigned decimal output.Open tool CalculatorRIPEMD-160 GeneratorCalculate a 160-bit RIPEMD digest in Hex or Base64 for specialized protocol and cryptocurrency compatibility checks.Open tool

Code & Token Tools

Inspect tokens and transform JavaScript without silently executing untrusted input.

4 tools

CalculatorJavaScript Eval EncoderWrap JavaScript as a character-code eval expression or recover the source text without running the submitted code.Open tool CalculatorJavaScript ObfuscatorObfuscate JavaScript you own with selectable low, balanced, or high presets and copy the transformed source locally.Open tool CalculatorJavaScript PackerCreate a compact Base64 runtime wrapper for JavaScript or unpack wrappers produced by this page without executing them.Open tool CalculatorJWT Decoder & VerifierDecode JWT headers and claims, inspect timestamps, and optionally verify an HMAC signature with a supplied secret.Open tool

Legacy Compatibility

Read or reproduce older formats behind visible warnings; use modern authenticated encryption for new work.

5 tools

CalculatorXOR Cipher ToolApply a repeating UTF-8 key to text, produce Base64 ciphertext, and reverse results generated with the same key.Open tool CalculatorRabbit Cipher ToolEncrypt or decrypt CryptoJS-compatible Rabbit ciphertext for legacy interoperability with an explicit compatibility warning.Open tool CalculatorRC4 Cipher ToolRead or produce RC4-compatible ciphertext for legacy migration work, with Base64 output and prominent deprecation guidance.Open tool CalculatorDES Cipher ToolEncrypt or decrypt DES-compatible text for old formats while clearly identifying the 56-bit cipher as obsolete.Open tool CalculatorTriple DES ToolRead or reproduce Triple DES ciphertext for compatibility work while directing new designs to authenticated AES-GCM.Open tool

Text, Privacy & Server Utilities

Create reversible text transforms, basic obfuscation, and server-compatible password records.

4 tools

Calculator24-Symbol Text CipherTurn UTF-8 text into a reversible sequence drawn from 24 visible symbols, then decode sequences created by this page.Open tool CalculatorText Steganography ToolHide UTF-8 text as zero-width characters inside visible cover text, or reveal payloads created by this browser tool.Open tool CalculatorEmail Address ObfuscatorConvert an email address into copyable numeric HTML entities without adding JavaScript or uploading the address.Open tool Calculatorhtpasswd Hash GeneratorGenerate an Apache-compatible bcrypt or legacy SHA-1 password record with a username and visible format guidance.Open tool

METHOD BEFORE OUTPUT

Cryptography tools should state what protection they actually provide

These 33 browser tools cover password creation, authentication codes, modern encryption, signatures, classical ciphers, hashes, checksums, token inspection, code transformation, and carefully labeled legacy compatibility. Every page starts with the underlying user task and the precise operation that produces its result. Encoding is never called encryption, a digest is never described as reversible, and decoding a JSON Web Token is kept separate from verifying its signature.

Ordinary inputs remain inside the current browser tab. Native Web Crypto handles AES-GCM, RSA, PBKDF2, HMAC, SHA digests, and cryptographic randomness. Small open-source libraries are loaded only for algorithms the browser does not expose, including SM2, SM4, RIPEMD-160, Keccak, SHAKE, bcrypt, and older compatibility formats. No password, private key, TOTP seed, plaintext, ciphertext, or result is sent to NexaCurrent for processing.

Modern protection needs authentication

The AES page uses AES-256-GCM, a fresh 96-bit IV, and a password-derived key with a fresh salt. GCM authenticates the encrypted text, so a wrong password or modified envelope fails instead of producing plausible garbage. The RSA page separates OAEP encryption from PSS signatures and limits the operation to short text because RSA is normally used to protect small session material rather than whole files.

TOTP seeds and private keys can grant access to real systems. The interface therefore treats them as secrets, never saves them as tool history, and gives visitors a clear reminder to clear the tab. Browser-generated keys are useful for testing and learning, but they are not certificates or substitutes for an organization's key-management process.

Hashes, MACs, and checksums answer different questions

SHA, Keccak, SHAKE, MD5, and RIPEMD-160 create deterministic digests. HMAC additionally uses a shared secret to authenticate a message. CRC-32 is designed to catch common accidental changes, not hostile tampering. MD5 and SHA-1 remain visible only where old formats require them, with a warning that their collision resistance is inadequate for modern signatures or security decisions.

Password storage is another separate problem. Fast general hashes are poor password verifiers because attackers can evaluate them cheaply. The htpasswd page defaults to bcrypt, while its SHA-1 output is explicitly marked as legacy compatibility. The password strength page estimates guess patterns but cannot know whether a password has been privately reused, stolen, or exposed by malware.

Legacy and classical tools are migration aids

Caesar, Vigenère, Hill, Rail Fence, ROT, repeating-key XOR, symbol substitution, and zero-width steganography are educational transforms. Their rules are public and their key spaces or patterns are easy to recover. Rabbit, RC4, DES, and Triple DES pages exist for controlled migration or old test fixtures; they direct new work to authenticated AES-GCM rather than presenting historical compatibility as current security.

Code packing and obfuscation can slow casual reading but cannot hide an API key shipped to a browser. The JavaScript decoder and unpacker accept only wrappers generated by this site and do not execute submitted source. Visitors should still review transformed code, restrict work to code they own, and use ordinary access control for genuine secrets.

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