Stampulator - the Stamp Calculator

About stampulator

This page calculates how many 1st/2nd class stamps you need for large letters and parcels.

Read my blog about why I created this here. When Royal Mail prices change please prompt me (email via my blog or twitter message to @srooteu) and I'll update the calculations. thanks!

Can you help please?

Stampulator is free. If you want to say thank you it would mean a lot to me if you would donate to my 2022 Expedition W3W challenge where I climb a mountain and ALL of your donations get split between 3 great charities. You can see a video of me explaining how the challange camea about at

Printable page

I designed this page to be printable. It makes for a very long poster, useful for quick reference.

Which stamps do you have?

By default, it's assumed you have the standard UK 1st (95p), 2nd (68p), Large 1st (£1.45p) and Large 2nd (£1.05p) which are are the April 2022 prices from Royal Mail (link also includes size and weight limits). Alternatively, enter the values of the stamps you have here and press submit. If you don't need all 4 values use a high number like 9999 so it won't be suggested in the calculation. If you'd like a page for a different country or values comment on my blog and I'll see what I can do.


Known limitations: Can only use up to 9 of each type of stamp (thus 36 stamps in total)

Your target values 129

UK Standard Services

Size Weight (up to) First Class Second Class
Letter 100g 95 68
Large Letter 100g 145 105
250g 205 165
500g 265 215
750g 330 270
Small Parcel 2kg 445 335
Medium Parcel 2kg 695 535
10kg 795 695
20kg 1295 1045

UK Signed for

Size Weight (up to) First Class Second Class
Letter 100g 235 208
Large Letter 100g 285 245
250g 345 305
500g 405 355
750g 470 410
Small Parcel 2kg 555 445
Medium Parcel 2kg 805 645
10kg 905 805
20kg 1405 1155