Standard letters up to 3.5 oz.
Pick a mail type, enter the weight in ounces, and choose your mailing date.
About the postage rate stamp counter
The postage rate stamp counter tells you how many stamps to put on a letter or postcard so it goes out with enough postage. Choose the mail type, enter the weight for a letter, pick a mailing date, and the tool reports the number of Forever stamps (for letters) or postcard stamps (for postcards) along with the postage that count covers. It is handy when you are mailing a multi-page letter, a greeting card, or a stack of postcards and are not sure one stamp is enough.
Stamp counts are based on USPS First-Class Mail pricing for standard letters up to 3.5 ounces and standard postcards up to 1 ounce. Postage rates change over time, so treat the figures as general guidance and confirm the current price at USPS before you mail. The tool runs in your browser and does not store anything you enter.
How to use
- Choose Letter or Postcard under Mail type. The weight field is active for letters and fixed for postcards.
- For a letter, enter its weight in ounces (up to 3.5). Heavier letters need additional postage, which the tool accounts for.
- Pick the date you plan to mail it using the mailing date field.
- Press Count stamps needed to see the recommended stamp count and the postage it covers.
- If your mailing date is more than six months out, note the reminder to re-check the rate, since USPS pricing may have changed by then.
Worked examples
1 oz letter = 1 Forever stamp
A standard one-page or two-page letter at or under one ounce is covered by a single Forever stamp.
2.5 oz letter rounds up to 3 oz for pricing
A heavier letter is priced by the next whole ounce, so the tool adds postage for each ounce above the first and tells you how many Forever stamps cover it.
Standard postcard = 1 postcard stamp
A standard-size postcard up to one ounce needs one postcard stamp, which costs less than a letter stamp.
Frequently asked questions
- How does the tool decide how many stamps I need?
- For a letter it rounds the weight up to the next whole ounce, adds the first-ounce price plus an additional-ounce price for each ounce beyond the first, then reports how many Forever stamps cover that postage. For a postcard it returns one postcard stamp for a standard postcard up to one ounce.
- Why does a heavier letter sometimes still need only one stamp?
- A Forever stamp covers the current one-ounce First-Class letter price, and there is some room before the postage owed exceeds that face value. Once an additional ounce pushes the postage past a single stamp's worth, the count rises to two and so on.
- Are the rates shown the exact current USPS prices?
- They reflect USPS First-Class Mail pricing as of the table review date shown with each result, but postage rates change over time. Use the count as general guidance and confirm the current price at USPS before mailing.
- Why does the tool ask for a mailing date?
- The date is a check so a recommendation is not based on a day that has already passed, and it triggers a reminder when your mailing date is far enough in the future that USPS rates may have changed before you send the item.
- What is the heaviest letter this covers?
- Up to 3.5 ounces, which is the standard First-Class Mail letter limit. Above that weight a piece is usually priced as a flat or parcel, so the tool points you to USPS to check those rates instead.
- Is a postcard always one stamp?
- For a standard-size postcard up to one ounce, yes, one postcard stamp. Oversized cards or ones over an ounce are priced as letters, so weigh anything that feels large or thick rather than assuming the postcard rate.
- Is anything I enter saved or sent anywhere?
- No. The stamp count is worked out on your device, and the weight and mailing date you enter are not collected or shared.
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