secp256k1 Public Key Derivation
Turn a secp256k1 private key into its public key — compressed, uncompressed, and raw X/Y coordinates. Runs entirely in your browser; keys never leave the page.
About this tool
Every secp256k1 private key has exactly one public key. This tool computes it by
multiplying the secp256k1 generator point G by your private key scalar —
public_key = private_key · G — and shows the resulting point in every encoding
you're likely to need.
Paste a private key as 64 hex characters (a leading 0x, spaces, and
underscores are fine) or as a WIF (Wallet Import Format, base58check — the
5…/K…/L… mainnet or 9…/c… testnet strings that wallets export). You get
back:
- Compressed SEC1 point — 33 bytes,
02or03prefix followed by the X coordinate. The prefix records whether Y is even (02) or odd (03), so the full point is recoverable from X alone. - Uncompressed SEC1 point — 65 bytes,
04prefix followed by X then Y. - X coordinate — the raw 32-byte X value. This is also the x-only public key used by Bitcoin Taproot (BIP340).
- Y coordinate — the raw 32-byte Y value.
- Y parity —
evenorodd, matching the compressed prefix.
The public-key point is the same no matter which chain you use it on (Bitcoin, Ethereum, Tron, and others all share secp256k1) — only the later address encoding differs.
Worked example
Private key 0000…0001 (the number 1) derives the secp256k1 generator point:
compressed: 0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798
uncompressed: 0479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8
x: 79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798
y: 483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8
y_parity: even
Choose a single Output option to get just that value as bare hex (handy for copy-paste into a script or wallet import).
Limits and privacy
- Derivation happens entirely in your browser via WebAssembly — the private key is never uploaded anywhere.
- The private key must be a valid secp256k1 scalar: non-zero and below the curve
order.
0000…0000and out-of-range values are rejected. - This tool derives from a key you already have — it does not generate random keys, and it does not produce Bitcoin/Ethereum addresses (those are separate steps that hash or encode the public key shown here).
FAQ
What's the difference between the compressed and uncompressed public key?
Both encode the same elliptic-curve point. The uncompressed form (04 + X +
Y) stores both coordinates: 65 bytes. The compressed form (02/03 + X)
stores only X plus a one-byte parity flag for Y: 33 bytes. Because the curve is
symmetric about the X axis, each X has just two possible Y values, so the parity
byte is enough to reconstruct Y. Modern Bitcoin uses compressed keys to save
space.
Why do compressed keys start with 02 or 03?
The prefix encodes the parity of the Y coordinate: 02 means Y is even, 03
means Y is odd. Together with the X coordinate that follows, this uniquely
identifies the point. The y_parity field in the "all" output tells you which
one applies.
Can I paste a WIF private key?
Yes. Paste a base58check WIF (the 5…/K…/L… mainnet or 9…/c… testnet
string a wallet exports) and the tool decodes the underlying 32-byte scalar. The
WIF's network byte and compression flag don't change the public-key point, so
both the compressed and uncompressed forms are always shown regardless of the
flag.
Is the X coordinate the same as a Taproot (x-only) public key?
Yes. Bitcoin Taproot (BIP340) uses x-only public keys — just the 32-byte X coordinate, with no prefix and no explicit Y. The X coordinate output is exactly that value.
Does this give me a Bitcoin or Ethereum address?
No — it stops at the public-key point. An address is a further step: Bitcoin hashes the compressed key (SHA-256 then RIPEMD-160) and base58check/bech32-encodes it; Ethereum takes the Keccak-256 of the 64-byte X‖Y and keeps the last 20 bytes. This tool focuses on deriving the raw public key those steps start from.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool secp256k1-pubkey-derive "0000000000000000000000000000000000000000000000000000000000000001"New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/secp256k1-pubkey-derive/?key=0000000000000000000000000000000000000000000000000000000000000001&format=allMachine-readable descriptor: tool.json — title + parameters JSON Schema for agents.