Free Google Ads calculator

Google Ads Bid Adjustment Calculator

Calculate your adjusted Google Ads bid. Enter a base bid and a percentage adjustment to see the resulting bid for a device, location, schedule, or audience.

Free · No signup · Updated June 2026

Your numbers

$
%

Use a negative value to bid down

Results

Adjusted bid
$2.40
Change
$0.40

Estimates for planning only. Your real results depend on audience, creative, and market conditions.

What it measures

A Google Ads bid adjustment is a percentage increase or decrease applied to your base bid for a specific device, location, schedule, or audience.

Formula

Adjusted bid = Base bid × (1 + Adjustment ÷ 100)

Worked example

A $2.00 base bid with a +20% adjustment becomes a $2.40 bid, a change of $0.40.

Typical benchmarks

Adjustment range
−100% to +900%
Mobile common range
−20% to +20%
Stacking
Multiplicative

How this calculator works

Adjusted bid = base bid × (1 + adjustment ÷ 100). A +20% adjustment on a $2 bid becomes $2.40; a −20% adjustment becomes $1.60. Layered adjustments multiply together.

Frequently asked questions

How do bid adjustments work? +

They raise or lower your bid by a percentage for specific signals like device, location, time, or audience, letting you bid more where conversions are likely.

Do bid adjustments stack? +

Yes. Multiple adjustments (e.g. device + location) multiply together, so a +20% and +10% combine to +32%.

Do bid adjustments work with Smart Bidding? +

Mostly no. With Target CPA, Target ROAS, or Maximize Conversions, Google sets bids automatically and ignores most manual adjustments except certain device and ad-schedule signals.

Can I set a −100% bid adjustment? +

Yes. A −100% adjustment effectively excludes that device, location, or audience because it reduces the bid to zero.

How do multiple bid adjustments combine? +

They multiply together. A +20% device adjustment and a +10% location adjustment combine to a +32% net change, not +30%.

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