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diff --git a/security-utils/src/main/java/com/yahoo/security/token/Token.java b/security-utils/src/main/java/com/yahoo/security/token/Token.java
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+++ b/security-utils/src/main/java/com/yahoo/security/token/Token.java
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+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.security.token;
+
+import com.yahoo.security.HKDF;
+
+import java.util.Objects;
+
+import static com.yahoo.security.ArrayUtils.toUtf8Bytes;
+
+/**
+ * <p>A token represents an arbitrary, opaque sequence of secret bytes (preferably from a secure
+ * random source) whose possession gives the holder the right to some resource(s) or action(s).
+ * For a token to be recognized it must be presented in its entirety, i.e. bitwise exact. This
+ * includes any (optional) text prefixes.
+ * </p><p>
+ * Only the party <em>presenting</em> the token should store the token secret itself; any
+ * parties that need to identify and/or verify the token should store <em>derivations</em>
+ * of the token instead (TokenFingerprint and TokenCheckHash, respectively).
+ * </p><p>
+ * A Token <em>object</em> is bound to a particular TokenDomain, but any given secret token
+ * string may be used to create many Token objects for any number of domains; it is opaque and
+ * not in and by itself tied to any specific domain.
+ * </p>
+ */
+public class Token {
+
+    private final TokenDomain domain;
+    private final String secretTokenString;
+    private final byte[] secretTokenBytes;
+    private final TokenFingerprint fingerprint;
+
+    Token(TokenDomain domain, String secretTokenString) {
+        this.domain = domain;
+        this.secretTokenString = secretTokenString;
+        this.secretTokenBytes = toUtf8Bytes(secretTokenString);
+        this.fingerprint = TokenFingerprint.of(this);
+    }
+
+    public static Token of(TokenDomain domain, String secretTokenString) {
+        return new Token(domain, secretTokenString);
+    }
+
+    public TokenDomain domain() { return domain; }
+    public String secretTokenString() { return secretTokenString; }
+    public TokenFingerprint fingerprint() { return fingerprint; }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        Token token = (Token) o;
+        // We assume that domain+fingerprint suffices for equality check.
+        // If underlying secret bytes checking is added it MUST use SideChannelSafe.arraysEqual()
+        // to avoid leaking secret data via timing side-channels.
+        return Objects.equals(domain, token.domain) &&
+                Objects.equals(fingerprint, token.fingerprint);
+    }
+
+    // Important: actual secret bytes must NOT be part of hashCode calculation, as that risks
+    // leaking parts of the secret to an attacker that can influence and observe side effects
+    // of the hash code.
+    @Override
+    public int hashCode() {
+        return Objects.hash(domain, fingerprint);
+    }
+
+    @Override
+    public String toString() {
+        // Avoid leaking raw token secret as part of toString() output
+        return "Token(fingerprint: %s)".formatted(fingerprint.toHexString());
+    }
+
+    /**
+     * Token derivations are created by invoking a HKDF (using HMAC-SHA256) that expands the
+     * original token secret to the provided number of bytes and the provided domain separation
+     * context. The same source token secret will result in different derivations when
+     * different contexts are used, but will always generate a deterministic result for the
+     * same token+#bytes+context combination.
+     */
+    byte[] toDerivedBytes(int nHashBytes, byte[] domainSeparationContext) {
+        var hkdf = HKDF.unsaltedExtractedFrom(secretTokenBytes);
+        return hkdf.expand(nHashBytes, domainSeparationContext);
+    }
+
+}