diff --git a/no_std_test/src/main.rs b/no_std_test/src/main.rs
index c0e114a..d98276c 100644
--- a/no_std_test/src/main.rs
+++ b/no_std_test/src/main.rs
@@ -1,16 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2019 by
-//   Elichai Turkel
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! # secp256k1 no-std test.
 //! This binary is a short smallest rust code to produce a working binary *without libstd*.
diff --git a/secp256k1-sys/build.rs b/secp256k1-sys/build.rs
index 2d9f844..c151217 100644
--- a/secp256k1-sys/build.rs
+++ b/secp256k1-sys/build.rs
@@ -1,16 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2015 by
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! # Build script
 
diff --git a/secp256k1-sys/src/lib.rs b/secp256k1-sys/src/lib.rs
index 87f9f6a..e8faa1c 100644
--- a/secp256k1-sys/src/lib.rs
+++ b/secp256k1-sys/src/lib.rs
@@ -1,17 +1,5 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
+
 //! # secp256k1-sys FFI bindings
 //! Direct bindings to the underlying C library functions. These should
 //! not be needed for most users.
diff --git a/secp256k1-sys/src/macros.rs b/secp256k1-sys/src/macros.rs
index 3f97245..ec225ab 100644
--- a/secp256k1-sys/src/macros.rs
+++ b/secp256k1-sys/src/macros.rs
@@ -1,17 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 /// Implement methods and traits for types that contain an inner array.
 #[macro_export]
diff --git a/secp256k1-sys/src/recovery.rs b/secp256k1-sys/src/recovery.rs
index 8899dc6..85db59e 100644
--- a/secp256k1-sys/src/recovery.rs
+++ b/secp256k1-sys/src/recovery.rs
@@ -1,17 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! # FFI of the recovery module
 
diff --git a/secp256k1-sys/src/types.rs b/secp256k1-sys/src/types.rs
index e457ec4..28ef0fb 100644
--- a/secp256k1-sys/src/types.rs
+++ b/secp256k1-sys/src/types.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: CC0-1.0
+
 #![allow(non_camel_case_types)]
 
 pub type c_int = i32;
diff --git a/src/constants.rs b/src/constants.rs
index 4b506f9..661ebaf 100644
--- a/src/constants.rs
+++ b/src/constants.rs
@@ -1,17 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! Constants related to the API and the underlying curve.
 //!
diff --git a/src/context.rs b/src/context.rs
index c59017b..f5a8396 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: CC0-1.0
+
 use core::marker::PhantomData;
 use core::mem::ManuallyDrop;
 use core::ptr::NonNull;
diff --git a/src/ecdh.rs b/src/ecdh.rs
index c0e1576..5f762d9 100644
--- a/src/ecdh.rs
+++ b/src/ecdh.rs
@@ -1,16 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2015 by
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! Support for shared secret computations.
 //!
diff --git a/src/ecdsa/mod.rs b/src/ecdsa/mod.rs
index c7083a1..f3ae5c0 100644
--- a/src/ecdsa/mod.rs
+++ b/src/ecdsa/mod.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: CC0-1.0
+
 //! Structs and functionality related to the ECDSA signature algorithm.
 //!
 
diff --git a/src/ecdsa/recovery.rs b/src/ecdsa/recovery.rs
index 003b7e1..abc6809 100644
--- a/src/ecdsa/recovery.rs
+++ b/src/ecdsa/recovery.rs
@@ -1,17 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! Provides a signing function that allows recovering the public key from the
 //! signature.
diff --git a/src/ecdsa/serialized_signature.rs b/src/ecdsa/serialized_signature.rs
index ab1f9e4..1b2a65a 100644
--- a/src/ecdsa/serialized_signature.rs
+++ b/src/ecdsa/serialized_signature.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: CC0-1.0
+
 //! Implements [`SerializedSignature`] and related types.
 //!
 //! DER-serialized signatures have the issue that they can have different lengths.
diff --git a/src/key.rs b/src/key.rs
index afa837e..c33637d 100644
--- a/src/key.rs
+++ b/src/key.rs
@@ -1,17 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! Public and secret keys.
 //!
diff --git a/src/lib.rs b/src/lib.rs
index b53ce4a..36dca7d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,17 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! Rust bindings for Pieter Wuille's secp256k1 library, which is used for
 //! fast and accurate manipulation of ECDSA signatures on the secp256k1
diff --git a/src/macros.rs b/src/macros.rs
index d5b78e9..4111b3f 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -1,17 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2014 by
-//   Dawid Ciężarkiewicz
-//   Andrew Poelstra
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 /// Implement methods and traits for types that contain an inner array.
 #[macro_export]
diff --git a/src/scalar.rs b/src/scalar.rs
index 57d1e25..4b2d0fc 100644
--- a/src/scalar.rs
+++ b/src/scalar.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: CC0-1.0
+
 //! Provides [`Scalar`] and related types.
 //!
 //! In elliptic curve cryptography scalars are non-point values that can be used to multiply
diff --git a/src/schnorr.rs b/src/schnorr.rs
index c29bb57..a8b7d67 100644
--- a/src/schnorr.rs
+++ b/src/schnorr.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: CC0-1.0
+
 //! Support for schnorr signatures.
 //!
 
diff --git a/src/secret.rs b/src/secret.rs
index 4faa152..f73bcd4 100644
--- a/src/secret.rs
+++ b/src/secret.rs
@@ -1,16 +1,4 @@
-// Bitcoin secp256k1 bindings
-// Written in 2021 by
-//   Maxim Orlovsky <orlovsky@pandoracore.com>
-//
-// To the extent possible under law, the author(s) have dedicated all
-// copyright and related and neighboring rights to this software to
-// the public domain worldwide. This software is distributed without
-// any warranty.
-//
-// You should have received a copy of the CC0 Public Domain Dedication
-// along with this software.
-// If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
-//
+// SPDX-License-Identifier: CC0-1.0
 
 //! Helpers for displaying secret values
 
diff --git a/src/serde_util.rs b/src/serde_util.rs
index e2751dd..3b851b2 100644
--- a/src/serde_util.rs
+++ b/src/serde_util.rs
@@ -1,3 +1,5 @@
+// SPDX-License-Identifier: CC0-1.0
+
 use core::fmt;
 use core::marker::PhantomData;
 use core::str::{self, FromStr};