diff --git a/src/jwt/produce.ts b/src/jwt/produce.ts
index 0c32f093b4..e6d356336a 100644
--- a/src/jwt/produce.ts
+++ b/src/jwt/produce.ts
@@ -105,11 +105,16 @@ export class ProduceJWT {
    * @param input "iat" (Issued At) Claim value to set on the JWT Claims Set. Default is current
    *   timestamp.
    */
-  setIssuedAt(input?: number | Date) {
+  setIssuedAt(input?: number | string | Date) {
     if (typeof input === 'undefined') {
       this._payload = { ...this._payload, iat: epoch(new Date()) }
     } else if (input instanceof Date) {
       this._payload = { ...this._payload, iat: validateInput('setIssuedAt', epoch(input)) }
+    } else if (typeof input === 'string') {
+      this._payload = {
+        ...this._payload,
+        iat: validateInput('setIssuedAt', epoch(new Date()) + secs(input)),
+      }
     } else {
       this._payload = { ...this._payload, iat: validateInput('setIssuedAt', input) }
     }
diff --git a/src/lib/secs.ts b/src/lib/secs.ts
index 8d9f07f7de..0abc825f8c 100644
--- a/src/lib/secs.ts
+++ b/src/lib/secs.ts
@@ -5,17 +5,19 @@ const week = day * 7
 const year = day * 365.25
 
 const REGEX =
-  /^(\d+|\d+\.\d+) ?(seconds?|secs?|s|minutes?|mins?|m|hours?|hrs?|h|days?|d|weeks?|w|years?|yrs?|y)$/i
+  /^(\+|\-)? ?(\d+|\d+\.\d+) ?(seconds?|secs?|s|minutes?|mins?|m|hours?|hrs?|h|days?|d|weeks?|w|years?|yrs?|y)(?: (ago|from now))?$/i
 
 export default (str: string): number => {
   const matched = REGEX.exec(str)
 
-  if (!matched) {
+  if (!matched || (matched[4] && matched[1])) {
     throw new TypeError('Invalid time period format')
   }
 
-  const value = parseFloat(matched[1])
-  const unit = matched[2].toLowerCase()
+  const value = parseFloat(matched[2])
+  const unit = matched[3].toLowerCase()
+
+  let numericDate: number
 
   switch (unit) {
     case 'sec':
@@ -23,29 +25,41 @@ export default (str: string): number => {
     case 'second':
     case 'seconds':
     case 's':
-      return Math.round(value)
+      numericDate = Math.round(value)
+      break
     case 'minute':
     case 'minutes':
     case 'min':
     case 'mins':
     case 'm':
-      return Math.round(value * minute)
+      numericDate = Math.round(value * minute)
+      break
     case 'hour':
     case 'hours':
     case 'hr':
     case 'hrs':
     case 'h':
-      return Math.round(value * hour)
+      numericDate = Math.round(value * hour)
+      break
     case 'day':
     case 'days':
     case 'd':
-      return Math.round(value * day)
+      numericDate = Math.round(value * day)
+      break
     case 'week':
     case 'weeks':
     case 'w':
-      return Math.round(value * week)
+      numericDate = Math.round(value * week)
+      break
     // years matched
     default:
-      return Math.round(value * year)
+      numericDate = Math.round(value * year)
+      break
+  }
+
+  if (matched[1] === '-' || matched[4] === 'ago') {
+    return -numericDate
   }
+
+  return numericDate
 }
diff --git a/test/jwt/encrypt.test.mjs b/test/jwt/encrypt.test.mjs
index ce1d74d5ee..3c040211a0 100644
--- a/test/jwt/encrypt.test.mjs
+++ b/test/jwt/encrypt.test.mjs
@@ -1,5 +1,6 @@
 import test from 'ava'
 import timekeeper from 'timekeeper'
+import { setters } from './time_setters.mjs'
 
 const { EncryptJWT, compactDecrypt, jwtDecrypt } = await import('#dist')
 
@@ -102,21 +103,19 @@ async function testJWTsetFunction(t, method, claim, value, duplicate = false, ex
   }
 }
 testJWTsetFunction.title = (title, method, claim, value) =>
-  `EncryptJWT.prototype.${method} called with ${value}${title ? ` (${title})` : ''}`
+  `EncryptJWT.prototype.${method} called with ${
+    value?.constructor?.name || typeof value
+  } (${value}) ${title ? ` (${title})` : ''}`
+
+for (const [method, claim, vectors] of setters(now)) {
+  for (const [input, output = input] of vectors) {
+    test(testJWTsetFunction, method, claim, input, false, output)
+  }
+}
 
-test(testJWTsetFunction, 'setIssuer', 'iss', 'urn:example:issuer')
 test('duplicated', testJWTsetFunction, 'setIssuer', 'iss', 'urn:example:issuer', true)
-test(testJWTsetFunction, 'setSubject', 'sub', 'urn:example:subject')
 test('duplicated', testJWTsetFunction, 'setSubject', 'sub', 'urn:example:subject', true)
-test(testJWTsetFunction, 'setAudience', 'aud', 'urn:example:audience')
 test('duplicated', testJWTsetFunction, 'setAudience', 'aud', 'urn:example:audience', true)
-test(testJWTsetFunction, 'setJti', 'jti', 'urn:example:jti')
-test(testJWTsetFunction, 'setIssuedAt', 'iat', 0)
-test(testJWTsetFunction, 'setIssuedAt', 'iat', undefined, undefined, now)
-test(testJWTsetFunction, 'setExpirationTime', 'exp', 0)
-test(testJWTsetFunction, 'setExpirationTime', 'exp', '10s', undefined, now + 10)
-test(testJWTsetFunction, 'setNotBefore', 'nbf', 0)
-test(testJWTsetFunction, 'setNotBefore', 'nbf', '10s', undefined, now + 10)
 
 test('EncryptJWT.prototype.setProtectedHeader', (t) => {
   t.throws(() => new EncryptJWT(t.context.payload).setProtectedHeader({}).setProtectedHeader({}), {
diff --git a/test/jwt/sign.test.mjs b/test/jwt/sign.test.mjs
index 2e7c472667..95a8daf1cd 100644
--- a/test/jwt/sign.test.mjs
+++ b/test/jwt/sign.test.mjs
@@ -1,5 +1,6 @@
 import test from 'ava'
 import timekeeper from 'timekeeper'
+import { setters } from './time_setters.mjs'
 
 const { SignJWT, compactVerify, jwtVerify } = await import('#dist')
 
@@ -99,18 +100,10 @@ async function testJWTsetFunction(t, method, claim, value, expected = value) {
   t.is(claims[claim], expected)
 }
 testJWTsetFunction.title = (title, method, claim, value) =>
-  `SignJWT.prototype.${method} called with ${value?.constructor?.name || typeof value}`
+  `SignJWT.prototype.${method} called with ${value?.constructor?.name || typeof value} (${value})`
 
-test(testJWTsetFunction, 'setIssuer', 'iss', 'urn:example:issuer')
-test(testJWTsetFunction, 'setSubject', 'sub', 'urn:example:subject')
-test(testJWTsetFunction, 'setAudience', 'aud', 'urn:example:audience')
-test(testJWTsetFunction, 'setJti', 'jti', 'urn:example:jti')
-test(testJWTsetFunction, 'setIssuedAt', 'iat', 0)
-test(testJWTsetFunction, 'setIssuedAt', 'iat', undefined, now)
-test(testJWTsetFunction, 'setIssuedAt', 'iat', new Date(now * 1000), now)
-test(testJWTsetFunction, 'setExpirationTime', 'exp', 0)
-test(testJWTsetFunction, 'setExpirationTime', 'exp', '10s', now + 10)
-test(testJWTsetFunction, 'setExpirationTime', 'exp', new Date(now * 1000), now)
-test(testJWTsetFunction, 'setNotBefore', 'nbf', 0)
-test(testJWTsetFunction, 'setNotBefore', 'nbf', '10s', now + 10)
-test(testJWTsetFunction, 'setNotBefore', 'nbf', new Date(now * 1000), now)
+for (const [method, claim, vectors] of setters(now)) {
+  for (const [input, output = input] of vectors) {
+    test(testJWTsetFunction, method, claim, input, output)
+  }
+}
diff --git a/test/jwt/time_setters.mjs b/test/jwt/time_setters.mjs
new file mode 100644
index 0000000000..1f80021870
--- /dev/null
+++ b/test/jwt/time_setters.mjs
@@ -0,0 +1,23 @@
+export function setters(now) {
+  const timeSetters = [
+    [0],
+    [new Date(now * 1000), now],
+    ['10s', now + 10],
+    ['+10s', now + 10],
+    ['-10s', now - 10],
+    ['+ 10s', now + 10],
+    ['- 10s', now - 10],
+    ['10s from now', now + 10],
+    ['10s ago', now - 10],
+  ]
+
+  return [
+    ['setIssuer', 'iss', [['urn:example:issuer']]],
+    ['setSubject', 'sub', [['urn:example:subject']]],
+    ['setAudience', 'aud', [['urn:example:audience']]],
+    ['setJti', 'jti', [['urn:example:jti']]],
+    ['setIssuedAt', 'iat', [[undefined, now], ...timeSetters]],
+    ['setExpirationTime', 'exp', timeSetters],
+    ['setNotBefore', 'nbf', timeSetters],
+  ]
+}
diff --git a/test/jwt/unsecured.test.mjs b/test/jwt/unsecured.test.mjs
index 9253d779b4..70ac4c90d4 100644
--- a/test/jwt/unsecured.test.mjs
+++ b/test/jwt/unsecured.test.mjs
@@ -1,7 +1,8 @@
 import test from 'ava'
 import timekeeper from 'timekeeper'
+import { setters } from './time_setters.mjs'
 
-const { UnsecuredJWT } = await import('#dist')
+const { UnsecuredJWT, decodeJwt } = await import('#dist')
 
 const now = 1604416038
 
@@ -47,18 +48,17 @@ test('new UnsecuredJWT()', (t) => {
 
 async function testJWTsetFunction(t, method, claim, value, expected = value) {
   const jwt = new UnsecuredJWT()[method](value).encode()
-  const { payload: claims } = UnsecuredJWT.decode(jwt)
+  const claims = decodeJwt(jwt)
   t.true(claim in claims)
   t.is(claims[claim], expected)
 }
 testJWTsetFunction.title = (title, method, claim, value) =>
-  `UnsecuredJWT.prototype.${method} called with ${value}`
+  `UnsecuredJWT.prototype.${method} called with ${
+    value?.constructor?.name || typeof value
+  } (${value})`
 
-test(testJWTsetFunction, 'setIssuer', 'iss', 'urn:example:issuer')
-test(testJWTsetFunction, 'setSubject', 'sub', 'urn:example:subject')
-test(testJWTsetFunction, 'setAudience', 'aud', 'urn:example:audience')
-test(testJWTsetFunction, 'setJti', 'jti', 'urn:example:jti')
-test(testJWTsetFunction, 'setIssuedAt', 'iat', 0)
-test(testJWTsetFunction, 'setIssuedAt', 'iat', undefined, now)
-test(testJWTsetFunction, 'setExpirationTime', 'exp', '10s', now + 10)
-test(testJWTsetFunction, 'setNotBefore', 'nbf', 0)
+for (const [method, claim, vectors] of setters(now)) {
+  for (const [input, output = input] of vectors) {
+    test(testJWTsetFunction, method, claim, input, output)
+  }
+}
diff --git a/test/unit/secs.test.mjs b/test/unit/secs.test.mjs
index eb2a2ce45f..229a060127 100644
--- a/test/unit/secs.test.mjs
+++ b/test/unit/secs.test.mjs
@@ -3,33 +3,109 @@ import test from 'ava'
 const { default: secs } = await import('#dist/lib/secs')
 
 test('lib/secs.ts', (t) => {
+  for (const sign of ['+', '+ ', '']) {
+    for (const v of ['sec', 'secs', 'second', 'seconds', 's']) {
+      t.is(secs(`${sign}1${v}`), 1)
+      t.is(secs(`${sign}1 ${v}`), 1)
+    }
+    for (const v of ['minute', 'minutes', 'min', 'mins', 'm']) {
+      t.is(secs(`${sign}1${v}`), 60)
+      t.is(secs(`${sign}1 ${v}`), 60)
+    }
+    for (const v of ['hour', 'hours', 'hr', 'hrs', 'h']) {
+      t.is(secs(`${sign}1${v}`), 3600)
+      t.is(secs(`${sign}1 ${v}`), 3600)
+    }
+    for (const v of ['day', 'days', 'd']) {
+      t.is(secs(`${sign}1${v}`), 86400)
+      t.is(secs(`${sign}1 ${v}`), 86400)
+    }
+    for (const v of ['week', 'weeks', 'w']) {
+      t.is(secs(`${sign}1${v}`), 604800)
+      t.is(secs(`${sign}1 ${v}`), 604800)
+    }
+    for (const v of ['years', 'year', 'yrs', 'yr', 'y']) {
+      t.is(secs(`${sign}1${v}`), 31557600)
+      t.is(secs(`${sign}1 ${v}`), 31557600)
+    }
+  }
+
+  for (const sign of ['-', '- ']) {
+    for (const v of ['sec', 'secs', 'second', 'seconds', 's']) {
+      t.is(secs(`${sign}1${v}`), -1)
+      t.is(secs(`${sign}1 ${v}`), -1)
+    }
+    for (const v of ['minute', 'minutes', 'min', 'mins', 'm']) {
+      t.is(secs(`${sign}1${v}`), -60)
+      t.is(secs(`${sign}1 ${v}`), -60)
+    }
+    for (const v of ['hour', 'hours', 'hr', 'hrs', 'h']) {
+      t.is(secs(`${sign}1${v}`), -3600)
+      t.is(secs(`${sign}1 ${v}`), -3600)
+    }
+    for (const v of ['day', 'days', 'd']) {
+      t.is(secs(`${sign}1${v}`), -86400)
+      t.is(secs(`${sign}1 ${v}`), -86400)
+    }
+    for (const v of ['week', 'weeks', 'w']) {
+      t.is(secs(`${sign}1${v}`), -604800)
+      t.is(secs(`${sign}1 ${v}`), -604800)
+    }
+    for (const v of ['years', 'year', 'yrs', 'yr', 'y']) {
+      t.is(secs(`${sign}1${v}`), -31557600)
+      t.is(secs(`${sign}1 ${v}`), -31557600)
+    }
+  }
+
   for (const v of ['sec', 'secs', 'second', 'seconds', 's']) {
-    t.is(secs(`1${v}`), 1)
-    t.is(secs(`1 ${v}`), 1)
+    t.is(secs(`1${v} ago`), -1)
+    t.is(secs(`1${v} from now`), 1)
+    t.is(secs(`1 ${v} ago`), -1)
+    t.is(secs(`1 ${v} from now`), 1)
   }
   for (const v of ['minute', 'minutes', 'min', 'mins', 'm']) {
-    t.is(secs(`1${v}`), 60)
-    t.is(secs(`1 ${v}`), 60)
+    t.is(secs(`1${v} ago`), -60)
+    t.is(secs(`1${v} from now`), 60)
+    t.is(secs(`1 ${v} ago`), -60)
+    t.is(secs(`1 ${v} from now`), 60)
   }
   for (const v of ['hour', 'hours', 'hr', 'hrs', 'h']) {
-    t.is(secs(`1${v}`), 3600)
-    t.is(secs(`1 ${v}`), 3600)
+    t.is(secs(`1${v} ago`), -3600)
+    t.is(secs(`1${v} from now`), 3600)
+    t.is(secs(`1 ${v} ago`), -3600)
+    t.is(secs(`1 ${v} from now`), 3600)
   }
   for (const v of ['day', 'days', 'd']) {
-    t.is(secs(`1${v}`), 86400)
-    t.is(secs(`1 ${v}`), 86400)
+    t.is(secs(`1${v} ago`), -86400)
+    t.is(secs(`1${v} from now`), 86400)
+    t.is(secs(`1 ${v} ago`), -86400)
+    t.is(secs(`1 ${v} from now`), 86400)
   }
   for (const v of ['week', 'weeks', 'w']) {
-    t.is(secs(`1${v}`), 604800)
-    t.is(secs(`1 ${v}`), 604800)
+    t.is(secs(`1${v} ago`), -604800)
+    t.is(secs(`1${v} from now`), 604800)
+    t.is(secs(`1 ${v} ago`), -604800)
+    t.is(secs(`1 ${v} from now`), 604800)
   }
   for (const v of ['years', 'year', 'yrs', 'yr', 'y']) {
-    t.is(secs(`1${v}`), 31557600)
-    t.is(secs(`1 ${v}`), 31557600)
+    t.is(secs(`1${v} ago`), -31557600)
+    t.is(secs(`1${v} from now`), 31557600)
+    t.is(secs(`1 ${v} ago`), -31557600)
+    t.is(secs(`1 ${v} from now`), 31557600)
   }
 
   t.throws(() => secs('1 fortnight'), {
     instanceOf: TypeError,
     message: 'Invalid time period format',
   })
+
+  t.throws(() => secs('= 1 second'), {
+    instanceOf: TypeError,
+    message: 'Invalid time period format',
+  })
+
+  t.throws(() => secs('- 1 second ago'), {
+    instanceOf: TypeError,
+    message: 'Invalid time period format',
+  })
 })