Elliptic Curve (ECDSA) Key Pair Generator
Generate P-256, P-384, and P-521 key pairs as PEM.
Free · no sign-up · runs locally·
About this tool
Elliptic-curve keys deliver the security of large RSA keys at a fraction of the size: a 256-bit EC key is roughly comparable to RSA-3072. This tool generates ECDSA signing key pairs on the NIST curves using the Web Crypto API, entirely on your device.
Export is standard PEM — PKCS#8 private, SPKI public — compatible with OpenSSL, JOSE/JWT libraries (ES256/ES384/ES512), and TLS tooling.
Like everything on encrypt.tools, this runs entirely in your browser — nothing you enter is transmitted or stored.
Do the same in a terminal
Reproduce or cross-check this tool with standard command-line utilities. For deterministic operations like hashing and encoding, the output matches exactly.
openssl genpkey -algorithm EC -pkeyopt ec_paramgen_curve:P-256 -out ec-private.pem
openssl pkey -in ec-private.pem -pubout -out ec-public.pemFrequently asked questions about ECC Key Generator
Why choose ECC over RSA?+
Elliptic-curve keys are much smaller for equivalent security — a 256-bit EC key roughly matches RSA-3072 — and are faster to generate and use. They're the modern default for TLS and JWT signing.
Which curve should I pick?+
P-256 (ES256) suits most uses. Choose P-384 or P-521 for higher security margins, at some performance cost. Match whatever your application or CA expects.
Are these keys for signing or encryption?+
These are ECDSA signing keys (used for JWT ES256/384/512 and TLS). For key agreement you'd use ECDH; for modern signing, see the Ed25519 generator.
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