Risk management policies - Risk Exposure (Details) - Currency risk £ in Millions	12 Months Ended
Dec. 31, 2023 GBP (£)	Dec. 31, 2022 GBP (£)
Cash Flow Hedges
Disclosure of nature and extent of risks arising from financial instruments [line items]
Hedging instrument, liabilities	£ (16.5)	£ (6.6)
Hedge Ratio	1	1
Hedge ineffectiveness (revaluation and retranslation of financial instruments)	£ 2.7	£ 2.9
Weighted average hedged rate for outstanding hedging instruments	4.40%	3.20%
Net Investment Hedges
Disclosure of nature and extent of risks arising from financial instruments [line items]
Hedge Ratio	1	1
Hedge ineffectiveness (revaluation and retranslation of financial instruments)	£ 1.9	£ 0.0
Weighted average hedged rate for the year (USD/GBP)	1.2731	1.2083
Hedging Instruments \| Cash Flow Hedges
Disclosure of nature and extent of risks arising from financial instruments [line items]
Nominal amount of hedging instrument	1,250.0	1,000.0
Hedge ineffectiveness (revaluation and retranslation of financial instruments)	£ 29.6	£ (41.4)
Hedging Instruments \| Net Investment Hedges
Disclosure of nature and extent of risks arising from financial instruments [line items]
Hedging instrument, liabilities		(46.9)
Hedging instrument, assets	48.2
Bond amount	1,873.9	1,666.8
Hedge ineffectiveness (revaluation and retranslation of financial instruments)	(110.1)	141.5
Non-Derivative Hedging Instrument \| Net Investment Hedges
Disclosure of nature and extent of risks arising from financial instruments [line items]
Hedging instrument, liabilities	(835.0)	(879.5)
Hedged Items \| Cash Flow Hedges
Disclosure of nature and extent of risks arising from financial instruments [line items]
Bond amount	1,250.0	1,000.0
Change in value of hedged item used to determine hedge effectiveness for outstanding hedging instruments	£ (32.4)	£ 38.5
Hedged Items \| Net Investment Hedges
Disclosure of nature and extent of risks arising from financial instruments [line items]
Nominal amount of hedging instrument	1,873.9	1,666.8
Change in value of hedged item used to determine hedge effectiveness for outstanding hedging instruments	£ 108.2	£ (141.5)

The average price of a hedging instrument. [Refer: Hedging instruments [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 23B
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_23B_b&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_AveragePriceOfHedgingInstrument
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

The average rate of a hedging instrument. [Refer: Hedging instruments [member]]

+ References

+ Details

Name:	ifrs-full_AverageRateOfHedgingInstrument
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The gain (loss) on the change in fair value of the hedged item used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24B
-Subparagraph a
-Clause iv
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24B_a_iv&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24B
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24B_b_i&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_GainLossOnChangeInFairValueOfHedgedItemUsedAsBasisForRecognisingHedgeIneffectiveness
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The gain (loss) on the change in fair value of the hedging instrument used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24A
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24A_c&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_GainLossOnChangeInFairValueOfHedgingInstrumentUsedAsBasisForRecognisingHedgeIneffectiveness
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of a hedging instrument, recognised as an asset. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24A
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24A_a&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_HedgingInstrumentAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of a hedging instrument, recognised as a liability. [Refer: Hedging instruments [member]]

+ References

+ Details

Name:	ifrs-full_HedgingInstrumentLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The nominal amount of a hedging instrument. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 23B
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_23B_a&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 24A
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_24A_d&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_NominalAmountOfHedgingInstrument
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_NotionalAmount
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Hedge Ratio

+ References

No definition available.

+ Details

Name:	wpp_HedgeRatio
Namespace Prefix:	wpp_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	ifrs-full_TypesOfRisksAxis=ifrs-full_CurrencyRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfHedgesAxis=ifrs-full_CashFlowHedgesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfHedgesAxis=wpp_NetInvestmentHedgesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_HedgingInstrumentsAxis=wpp_HedgingInstruments1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_HedgingInstrumentsAxis=wpp_NonDerivativeHedgingInstrumentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_HedgedItemsAxis=wpp_HedgedItems1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: