How our price comparison works

What we compare

We compare the price of a product on MyDIY with the price of the same product at other UK retailers. Same manufacturer, same model, same pack size. Where a retailer sells a different size, quantity or specification, we do not treat it as a match and it does not appear in the table.

We currently hold at least one competitor price for 11 products across 8 retailers we track.

Where the prices come from

Competitor prices are read from the retailers’ own public product pages by an automated tool that we run and maintain. Nothing is estimated, and nothing is supplied by the retailers themselves. If our tool cannot read a genuine price for a retailer — the page has changed, the product is delisted, or the price is hidden behind a login — that retailer simply does not appear for that product.

Do the prices include VAT and delivery?

All prices shown on MyDIY, ours and our competitors’, include VAT. Some trade merchants display prices excluding VAT on their own websites; where that is the case we add VAT at the current rate before comparing, so you are always comparing like with like.

To confirm before launch: whether comparison prices are quoted excluding delivery for every retailer, and how you want that stated here. Delivery charges differ by retailer, basket size and postcode, so they are not currently included in the comparison figure.

How we calculate the saving

The two figures we show are calculated like this:

Saving in pounds = the cheapest competitor price we hold, minus the MyDIY price.
Saving as a percentage = that difference, divided by the cheapest competitor price, expressed as a percentage.

We deliberately calculate the headline saving against the cheapest competitor, not the most expensive one. That is the most conservative honest figure: it is the least you would save by buying from us rather than shopping around. Where a dearer retailer is also in the table, you can see that price too, and we will say what the difference is — but the badge on a product always uses the cheaper, harder-to-beat number.

If MyDIY is not the cheapest price we hold for a product, we do not claim a saving at all. No badge, no “you save” line. The comparison table still shows every price we hold, so you can decide for yourself.

How often prices are updated

Prices are re-checked regularly. Where we hold the date a price was last checked we show it underneath the comparison table, so you can judge how current it is.

To confirm before launch: how often the scraper runs, so this page can state a specific refresh frequency. Once you decide, setting comparison.max_age_days in the site configuration will also stop any price older than that from being used in a comparison.

Prices change

Retailers change their prices whenever they like, and promotions come and go. A price we read this morning may not be the price you see this afternoon. We show the date we checked so you can see how fresh the figure is, and we would always encourage you to click through and check for yourself if a saving matters to your decision.

What we never do

We never invent a competitor price to make a saving look bigger.
We never show a “was” price that the product was not genuinely sold at.
We never claim a saving we cannot calculate from a real competitor price.
We never present a competitor as a seller of our product in our structured data — comparisons are information for you, not an offer from them.

Think we have got one wrong?

If a price on this site looks wrong, please tell us and we will check it. Send us a message with the product name and what you have seen elsewhere.