Page Speed Revenue Calculator
Estimate what a faster store is worth: seconds saved, to conversion rate, to extra revenue and profit per year.
Your numbers
Your result · updates as you type
Extra revenue per year
$37,800
Going from 4.5 s to 2.5 s saves 2 s. At your assumption of 5% more conversions per second saved, conversion rate moves from 1.5% to 1.65%: 45 more orders a month.
- Extra gross profit per year
- $18,900
- Payback on the work
- 1.9 months
- Break-even assumption
- 0.8% per second
This rests on your assumption, so test a range. For reference, Deloitte's 2020 study for Google (37 brands, 30 million sessions) measured 8.4% more retail conversions after a 0.1 s mobile speed gain. That was a small change, so don't multiply it across whole seconds.
Breakdown
- Seconds saved
- 2 s
- Conversion lift (2 × 5%)
- 10%
- Conversion rate
- 1.5% → 1.65%
- Orders per month
- 450 → 495
- Revenue per month
- $31,500 → $34,650
- Extra gross profit per year
- $18,900
- Cost of the work
- −$3,000
- Net in the first year
- $15,900
How the estimate works
Speed doesn't earn money by itself. It changes how many visitors buy. So the calculator turns the seconds you save into a conversion lift, using an assumption you set, and then into orders, revenue and profit.
Example
- Sessions per month
- 30,000
- Conversion rate
- 1.5% (450 orders)
- Average order value
- $70
- Load time
- 4.5 s now, 2.5 s after (2 s saved)
- Your assumption
- 5% more conversions per second saved
- Cost of the work
- $3,000
2 × 5% = a 10% lift, so conversion goes from 1.5% to 1.65%: 45 more orders a month. 45 × $70 × 12 = $37,800 extra revenue a year, or $18,900 of gross profit at a 50% margin. The work pays back in 1.9 months, and the assumption only needs to be 0.8% per second to break even in a year.
What the research says, and what it doesn't
The study most often quoted is Deloitte's Milliseconds Make Millions (2020), commissioned by Google. It analyzed four weeks of mobile data from 37 brands and 30 million sessions. For the 15 retail brands, a 0.1 s improvement across four speed metrics came with 8.4% more conversions and a 9.2% higher average order value.
- It measured a 0.1 s change. The study used a logarithmic regression model, so a full second isn't ten times the effect. Don't plug 84% per second into the calculator.
- It reported correlations, and only statistically significant ones. Brands where speed had little or no effect were left out of the results.
- This calculator leaves order value unchanged, to keep the estimate on the cautious side.
That's why the lift per second is your input, not a fixed number. Use the chart to see a range, and the break-even figure to see how little the work has to deliver.
Measuring your load time
- 01
Shopify
Go to Online Store → Themes for a summary, or Analytics → Reports for the full web performance report. It shows LCP, INP and CLS from real visitors over the last 30 days.
- 02
WooCommerce
Run your home page, a category page and a product page through PageSpeed Insights. Use the mobile LCP from real-user data where it's shown; lab scores from one test run are less reliable.
- 03
Pick a target
Google rates an LCP of 2.5 s or less, measured at the 75th percentile of page loads, as good. That makes 2.5 s a sensible target for most stores.
Speed work is one of the things I do for Shopify and WooCommerce stores: trimming apps and plugins, fixing how images and scripts load, and checking the result in real-user data. If the estimate above is worth chasing, my details are at the bottom of this page.
Questions people ask
How much revenue does a slow site lose?
There's no single figure that fits every store. Deloitte's 2020 study linked a 0.1 s mobile improvement to 8.4% more retail conversions, but that doesn't scale in a straight line, so test a range of assumptions.
Which load time should I use?
Mobile Largest Contentful Paint (LCP) from real visitors, where you have it. It's the metric Shopify's web performance report and Google's Core Web Vitals use for loading speed.
Why is the conversion lift an assumption?
Because the effect of speed depends on your audience, products and how slow you are now. A range of assumptions plus the break-even figure is more honest than one borrowed number.
Does a faster site raise order value too?
Deloitte saw a 9.2% higher average order value for retail brands with a 0.1 s gain. This calculator leaves AOV unchanged so the estimate stays conservative.
My store is already fast. Is speed work worth it?
If mobile LCP is already 2.5 s or less, there are fewer seconds to save, so the estimate will be modest. The CRO ROI calculator helps you compare it with other conversion work.
Related tools
Want this builtinto your store?
I'm Emmanuel, a Shopify and WooCommerce developer. If this tool pointed at something you'd rather have fixed for you (a faster store, cleaner product data, a migration, a custom feature), send me a note.
Emmanuel Asika
Shopify & WooCommerce developer, Dublin
I build and fix online stores: new builds, migrations, speed, SEO and the custom bits apps can't do.
Last reviewed 30 September 2026.
Sources: Deloitte for Google: Milliseconds Make Millions (2020) · web.dev: Largest Contentful Paint (LCP) · Shopify Help: Web performance dashboard