diff --git a/src/root.zig b/src/root.zig
index f58f489..2a61584 100644
--- a/src/root.zig
+++ b/src/root.zig
@@ -4,6 +4,7 @@ pub const bips = @import("bips/lib.zig");
 pub const hashes = @import("hashes/lib.zig");
 pub const secp256k1 = @import("secp256k1");
 pub const types = @import("types/lib.zig");
+pub const wif = @import("wif/wif.zig");
 
 test {
     const std = @import("std");
diff --git a/src/wif/lib.zig b/src/wif/lib.zig
new file mode 100644
index 0000000..35f2ae0
--- /dev/null
+++ b/src/wif/lib.zig
@@ -0,0 +1 @@
+pub const Wif = @import("wif.zig").WIF;
diff --git a/src/wif/wif.zig b/src/wif/wif.zig
new file mode 100644
index 0000000..d6dd3b5
--- /dev/null
+++ b/src/wif/wif.zig
@@ -0,0 +1,115 @@
+const PrivateKey = @import("../bips/bip32/key.zig").PrivateKey;
+const Network = @import("../bips/bip32/bip32.zig").Network;
+const std = @import("std");
+const Base58Encoder = @import("../base58/base58.zig").Encoder;
+const secp256k1 = @import("secp256k1");
+
+/// WIF as defined in https://en.bitcoin.it/wiki/Wallet_import_format
+pub const WIF_PREFIX_MAINNET: u8 = 0x80;
+pub const WIF_PREFIX_TESTNET: u8 = 0xef;
+pub const WIF_COMPRESSED_FLAG: u8 = 0x01;
+
+pub const WIFDecodeError = error{};
+
+pub const WIF = struct {
+    const Self = @This();
+    inner: []u8,
+
+    pub fn fromPrivateKey(private_key: PrivateKey) !Self {
+        const max_size = 1 + 32 + 1 + 4; // prefix + key  + compressed flag + checksum
+        var actual_size: u8 = max_size - 1;
+        if (private_key.compressed) {
+            actual_size += 1;
+        }
+        var buf = [_]u8{0} ** max_size;
+
+        if (private_key.network == Network.MAINNET) {
+            buf[0] = WIF_PREFIX_MAINNET;
+        } else {
+            buf[0] = WIF_PREFIX_TESTNET;
+        }
+
+        @memcpy(buf[1..33], private_key.inner.data[0..32]);
+
+        if (private_key.compressed) {
+            buf[33] = WIF_COMPRESSED_FLAG;
+        }
+
+        var sha256 = std.crypto.hash.sha2.Sha256.init(.{});
+        var out256: [std.crypto.hash.sha2.Sha256.digest_length]u8 = undefined;
+
+        sha256.update(buf[0 .. actual_size - 4]);
+        sha256.final(&out256);
+
+        sha256 = std.crypto.hash.sha2.Sha256.init(.{});
+
+        sha256.update(out256[0..std.crypto.hash.sha2.Sha256.digest_length]);
+        sha256.final(&out256);
+
+        @memcpy(buf[actual_size - 4 .. actual_size], out256[0..4]);
+
+        // base58 encode
+        var encoder = Base58Encoder{};
+        var encode_buf = [_]u8{0} ** 52; // max wif len is 52
+        const encode_size = encoder.encode(buf[0..actual_size], &encode_buf);
+        const wif = WIF{
+            .inner = encode_buf[0..encode_size],
+        };
+        return wif;
+    }
+
+    pub fn toString(self: WIF) []u8 {
+        return self.inner;
+    }
+
+    pub fn fromString(wif: []const u8) !WIF {
+        _ = wif;
+        return WIF{ .inner = undefined };
+    }
+
+    pub fn toPrivateKey(self: WIF) !PrivateKey {
+        _ = self;
+        return PrivateKey{ .network = Network.MAINNET, .compressed = false, .inner = secp256k1.SecretKey{ .data = [_]u8{0} ** 32 } };
+    }
+};
+
+test "WIF with compressed private key" {
+    const privateKey = PrivateKey{ .network = Network.MAINNET, .compressed = true, .inner = try secp256k1.SecretKey.fromString("7bea4d472aa93e49321bbde5db88b126b9435482e1f39d84664530a5f40408cd") };
+    const wif = try WIF.fromPrivateKey(privateKey);
+    const expected = "L1NawHPsZVHsnW4DUBC7K36LzXfcsLck85fMSoEGyT4LMZv9xSjD";
+    const actual = wif.toString();
+    try std.testing.expectEqualSlices(u8, expected[0..], actual[0..]);
+}
+
+test "WIF with uncompressed private key 2" {
+    const privateKey = PrivateKey{ .network = Network.MAINNET, .compressed = false, .inner = try secp256k1.SecretKey.fromString("0C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D") };
+    const wif = try WIF.fromPrivateKey(privateKey);
+    const expected = "5HueCGU8rMjxEXxiPuD5BDku4MkFqeZyd4dZ1jvhTVqvbTLvyTJ";
+    const actual = wif.toString();
+    try std.testing.expectEqualSlices(u8, expected[0..], actual[0..]);
+}
+
+test "WIF with uncompressed private key" {
+    const privateKey = PrivateKey{ .network = Network.MAINNET, .compressed = false, .inner = try secp256k1.SecretKey.fromString("46605abb568e1566834e7ee57e271964534d8fc3b23ca5f546b081ad7e233671") };
+    const wif = try WIF.fromPrivateKey(privateKey);
+    const expected = "5JMHFZHuMcVnqVBARmg3jW3LMxdB6qbJtesC5xhXRji6wabvbWu";
+    const actual = wif.toString();
+    // std.debug.print("actual========: {s}\n", .{actual});
+    try std.testing.expectEqualSlices(u8, expected[0..], actual[0..]);
+}
+
+test "WIF with compressed testnet private key" {
+    const privateKey = PrivateKey{ .network = Network.TESTNET, .compressed = true, .inner = try secp256k1.SecretKey.fromString("46605abb568e1566834e7ee57e271964534d8fc3b23ca5f546b081ad7e233671") };
+    const wif = try WIF.fromPrivateKey(privateKey);
+    const expected = "cPwWCAXTX3NLUSq7zjzURugN5jp5FDa832H13KJNoJARUPsaTJ9G";
+    const actual = wif.toString();
+    try std.testing.expectEqualSlices(u8, expected[0..], actual[0..]);
+}
+
+test "WIF with uncompressed testnet private key" {
+    const privateKey = PrivateKey{ .network = Network.TESTNET, .compressed = false, .inner = try secp256k1.SecretKey.fromString("46605abb568e1566834e7ee57e271964534d8fc3b23ca5f546b081ad7e233671") };
+    const wif = try WIF.fromPrivateKey(privateKey);
+    const expected = "927uqJ7SwqZvoYgT47Zxc6bJ1cytG18WEbj9Ab42mUT9icaLVhF";
+    const actual = wif.toString();
+    try std.testing.expectEqualSlices(u8, expected[0..], actual[0..]);
+}