Is SHA-3 just a newer, more secure version of SHA-2?

Not exactly, SHA-2 has no known practical break, so SHA-3 wasn't created to replace a broken algorithm. NIST ran the SHA-3 competition (won by Keccak, designed by Bertoni, Daemen, Peeters, and Van Assche) specifically to have a structurally independent backup: SHA-2 is built on the Merkle–Damgård construction, while SHA-3 uses an entirely different sponge construction, so a future attack against one family's underlying structure wouldn't automatically threaten the other.

Why compute all four SHA-3 lengths at once?

For the same reason as this category's SHA-2 family tool: comparing lengths, filling in a form that just says "SHA-3", or exploring the family for the first time is easier with all four side by side from one input. If you already know you need exactly one length, the dedicated SHA3-224, SHA3-256, SHA3-384, or SHA3-512 tools are more direct.

Is raw Keccak the same as SHA-3?

No, and this trips people up constantly. NIST changed the padding rule when standardizing Keccak as SHA-3, adding a 0x06 domain-separation byte that the original Keccak submission didn't use. That means raw Keccak-256 (what Ethereum uses) and SHA3-256 (what this tool computes) produce different digests for identical input despite sharing the same underlying permutation. This category has a separate Keccak Hash Calculator for the raw variant.

Does this tool send my text to a server?

No. All four digests are computed entirely in your browser using @noble/hashes, an audited JavaScript library, so nothing you type here is transmitted anywhere.

SHA-3 Hash Calculator - SHA3-224/256/384/512 at Once

Overview

Introduction

SHA-3 is a family of four hash functions, not a single algorithm, all built on the Keccak sponge construction NIST selected in a public competition and standardized in FIPS 202 in 2015.

This tool computes all four common SHA-3 lengths, SHA3-224, SHA3-256, SHA3-384, and SHA3-512, from a single input in one pass, so you can compare them directly or grab whichever length you need.

What Is SHA-3 Hash Calculator?

SHA-3 is NIST's second standardized hash family, selected via public competition specifically to provide a structurally independent alternative to SHA-2's Merkle–Damgård design, using Keccak's sponge construction instead.

Like SHA-2, it comes in four common output sizes (224, 256, 384, 512 bits); unlike SHA-2, all four sizes share the same underlying 1600-bit permutation and differ only in rate/capacity split and output truncation.

How SHA-3 Hash Calculator Works

Your UTF-8 text is independently run through this category's existing SHA3-224, SHA3-256, SHA3-384, and SHA3-512 implementations (from @noble/hashes), each absorbing the input into a Keccak sponge at its own rate and squeezing out the appropriate digest length.

The four resulting hex digests are combined into one labeled, multi-line output so you can read or copy any of them without running four separate tools.

When To Use SHA-3 Hash Calculator

Use this when you want a quick side-by-side comparison of SHA-3 lengths, or when a spec just says "SHA-3" and you need to see all the reasonable candidates at once.

If you already know you need exactly one length, e.g., matching a published SHA3-256 checksum, the dedicated single-length tools are more direct.

Often used alongside SHA3-224 Hash Calculator, SHA3-256 Hash Calculator and SHA3-384 Hash Calculator.

Features

Advantages

Saves running the same input through four separate tools when comparing SHA-3 lengths.
Makes clear that all four sizes share one sponge permutation, unlike SHA-2's two separate word-size halves.
Reuses this category's already-audited per-length implementations rather than adding a new code path.

Limitations

Not a single canonical "SHA-3 hash"; if a system expects exactly one specific length, you still need to pick the matching line from the output.
Doesn't cover SHAKE128/SHAKE256 (SHA-3's extendable-output functions) or raw Keccak; separate tools in this category handle those.

Examples

Hashing a short greeting across all four lengths

Input

Hello, world!

Output

SHA3-224: 6a33e22f20f16642697e8bd549ff7b759252ad56c05a1b0acc31dc69
SHA3-256: f345a219da005ebe9c1a1eaad97bbf38a10c8473e41d0af7fb617caa0c6aa722
SHA3-384: 6ba9ea268965916f5937228dde678c202f9fe756a87d8b1b7362869583a45901fd1a27289d72fc0e3ff48b1b78827d3a
SHA3-512: 8e47f1185ffd014d238fabd02a1a32defe698cbf38c037a90e3c0a0a32370fb52cbd641250508502295fcabcbf676c09470b27443868c8e5f70e26dc337288af

All four SHA-3 lengths of the same 13-byte UTF-8 input, computed in one pass and clearly labeled.

Best Practices & Notes

Best Practices

Default to SHA3-256 unless you have a specific reason to pick a different length or need SHAKE's variable output instead.
When matching an externally published checksum, confirm which exact SHA-3 length it used, and whether it's actually raw Keccak rather than standardized SHA-3, before comparing.
Use the SHA-2 Hash Calculator alongside this one if you want to compare the two structurally different NIST-standardized families for the same input.

Developer Notes

This tool adds no new hashing logic: it calls this category's existing calculateSha3224Hash/calculateSha3256Hash/calculateSha3384Hash/calculateSha3512Hash functions (all backed by @noble/hashes) and formats the four results into one labeled multi-line string. If any individual digest fails to compute, the whole tool reports an error rather than a partial result.

SHA-3 Hash Calculator Use Cases

Comparing all four SHA-3 lengths for the same input side by side
Quickly seeing which length a partially specified "SHA-3 checksum" in documentation might refer to
Teaching the SHA-3 family's sponge construction and its four output sizes
Cross-checking against SHA-2 outputs when evaluating hash function diversity for a design

Common Mistakes

Treating "SHA-3" and "SHA3-256" as synonyms when a spec might mean a different family length.
Confusing raw Keccak-256 (used by Ethereum) with standardized SHA3-256; they differ due to a padding change and produce different digests for the same input.
Assuming SHA-3 replaces SHA-2 because it's newer; SHA-2 has no known practical break and both remain NIST-approved.

Tips

Need the raw, pre-standardization Keccak variant instead? Use the dedicated Keccak Hash Calculator.
Pair with the SHA-2 Hash Calculator to compare Merkle–Damgård (SHA-2) against sponge-construction (SHA-3) output for the same text.

SHA-3 Hash Calculator