USPS Postage Calculator – Cost to Mail Letters and Packages
Postage is simple arithmetic wearing a uniform: a first ounce, a price for every extra ounce, and as many pieces as you are sending. This calculator does that adding-up for letters and packages alike — and it is honest about the one thing most postage pages are not. USPS changes its prices, so instead of pretending to know today’s rates, it lets you enter the rates you are actually paying. The defaults are a labelled example: the letter prices USPS set on 13 July 2025, 78 cents for the first ounce and 29 cents for each additional ounce. Swap in your own rates and every number follows.
What you are mailing
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Your postage
The maths, line by line
A clean, whole-ounce letter
Exactly 3 oz, so nothing is rounded: $0.78 for the first ounce and 2 extra ounces at $0.29. One reminder that applies to every figure on this page — these are the rates you entered, and the defaults are the example letter rates USPS set in July 2025. If prices have moved since, or your meter gives you different ones, type yours in and the whole page follows.
What a letter costs, ounce by ounce
The whole of letter pricing is one ladder: the first ounce, then the same extra amount for every billed ounce after it — until the ladder ends at 3.5 oz, the heaviest letter there is.
At your rates, each extra billed ounce adds $0.29, so the ladder climbs $0.78, $1.07, $1.36 and $1.65. Your letter bills as 3 oz — the highlighted rung.
Why this page will not quote you a package price from thin air
Package postage is not one price — it is a weight, three dimensions, a distance and a service level folded together, and any page that shows you a tidy zone chart without asking for yours is guessing with your money. So this calculator takes the honest route: you bring the per-package price from the label you actually bought, or from usps.com, and it does the multiplying and the adding — the part that is genuinely arithmetic — exactly, for as many pieces as you are sending.
Pairs well with this calculation
The measuring and costing that happens around a mailing.
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How to work out your postage in three steps
Get the rates you actually pay
Two numbers run the letter side: the first-ounce price and the additional-ounce price. They are printed on usps.com and in the Postal Explorer, and your meter tape or label summary shows the ones you really pay — retail, metered and commercial prices all differ, so use yours, not a stranger’s screenshot.
Weigh one piece, honestly
Envelope, contents, the lot, on a kitchen scale. Remember the rounding: any fraction of an ounce bills as a whole extra ounce, so a 2.2 oz letter pays the 3 oz price. And if the scale says more than 3.5 oz, the piece has left letter pricing behind entirely.
Multiply it out
Per-letter postage times the number of letters, per-package price times the number of packages, then add the two. That is your postage budget before you reach the counter — no surprises, no short-paid mail coming back.
How the postage calculator works
per letter = first ounce + (billed ounces − 1) × extra-ounce price · total = per letter × letters + package price × packages
The example on this page. A 3 oz letter at the example rates: the weight is a whole number of ounces, so it bills as 3 oz. The first ounce is $0.78, the two extra ounces are 2 × $0.29 = $0.58, and the letter costs $0.78 + $0.58 = $1.36 — which is exactly the 3 oz letter price USPS published in its July 2025 price change. Ten of them come to $13.60.
Why fractions are never free. A wedding invitation at 2.2 oz does not pay for 2.2 oz. USPS bills any fraction as the next whole ounce, so the invitation pays the 3 oz price — the same $1.36. Weigh before you seal: a heavier envelope, a second insert or a rigid card can quietly push a piece over an ounce line.
The ceiling at 3.5 oz. The heaviest letter still bills on the ladder: 3.5 oz costs $0.78 + 3 × $0.29 = $1.65, again the published price. One step further, at 3.6 oz, the piece is not a letter at all — a flexible one prices as a large envelope (flat) by the ounce, and a thick or rigid one can price as a parcel. That is why this calculator flags the weight instead of silently extending the ladder past its end.
The package side. Four orders, each labelled at $9.50, are 4 × $9.50 = $38.00 of postage. Add the letters and the whole mailing is $13.60 + $38.00 = $51.60 — the total at the top of this page. Change any rate, weight or quantity and every line rebuilds itself.
Going deeper
USPS reprices its products regularly — the change behind this page’s defaults took effect on 13 July 2025, when the first ounce of a letter rose from 73 to 78 cents and each additional ounce from 28 to 29 cents. Any calculator that hard-codes “the” postage price starts going stale the day it is published, and a stale postage figure is worse than none: the mail still travels, and the shortage lands on you or your recipient.
There is also no single price to hard-code. The same 1 oz letter costs 78 cents at the retail counter, 74 cents through a meter at those July 2025 prices, and less again on commercial rates. So this page asks for your two numbers instead. They are printed at usps.com under Mailing and Shipping Prices and in the Postal Explorer, and your own meter tape or label summary shows the ones that actually leave your account. One comfort: a Forever stamp always covers the first ounce of a standard letter, whatever you paid for it — it is the extra ounces that need topping up.
Letter pricing has a hard ceiling: 3.5 oz. Up to that weight, the first-ounce-plus-extra-ounces ladder on this page is the whole story. Past it, a piece that is still flat and flexible prices as a large envelope — a “flat” — which is priced by the ounce up to 13 oz on a different, higher ladder. A piece that is thick, rigid or lumpy can be priced as a parcel whatever the scale says.
Shape has a vote as well as weight. USPS can add a nonmachinable surcharge to letters that cannot run through its sorting machines — pieces that are rigid, square, lumpy or closed with a clasp are the usual suspects — so two letters of identical weight can legitimately cost different amounts. The practical habit: weigh everything, keep an eye on the 3.5 oz line, and if a piece is anywhere near it, expect flat pricing and budget for that instead.
The ounce ladder: one letter at five weights
The rates below are this page’s example defaults — the USPS retail letter rates from the price change of 13 July 2025, when the first ounce rose from 73 to 78 cents and each additional ounce from 28 to 29 cents. They are labelled examples on the page itself, because USPS reprices regularly: always check the current figures at usps.com before you mail. Every row was run through this page’s own calculator at those example rates.
| Letter weight | Billed ounces | Postage per letter | Ten letters |
|---|---|---|---|
| 1 oz | 1 oz | $0.78 | $7.80 |
| 2.2 oz | 3 oz | $1.36 | $13.60 |
| 3 oz (the default) | 3 oz | $1.36 | $13.60 |
| 3.5 oz | 4 oz by ceiling* | $1.65 | $16.50 |
| 3.6 oz | — | Not a letter | — |
*At 3.5 oz the ceiling rounds the weight up to 4 billed ounces, so the price is $0.78 + 3 × $0.29 = $1.65. Past 3.5 oz the piece leaves letter pricing entirely.
The row that teaches the most is the second one. A 2.2 oz letter pays the 3 oz price — $1.36, identical to a letter that actually weighs 3 oz — because USPS bills any fraction of an ounce as a whole extra ounce. The rounding is always up, never to the nearest: a 2.1 oz letter and a 2.9 oz letter both pay the 3 oz price, and the only weight that escapes the rounding is a whole number of ounces. That is why the page’s own steps say to weigh before you seal: a heavier envelope, a second insert or a rigid card can quietly push a piece over an ounce line, and the extra ounce costs the same whether the excess is a tenth of an ounce or nine-tenths. The 1 oz row shows the other end of the ladder — a whole-ounce letter pays exactly the first-ounce price, $0.78, with nothing rounded — and the 3.5 oz row shows the ceiling: $0.78 + 3 × $0.29 = $1.65, the heaviest letter that still bills on the ladder at all.
The 3.6 oz row is not a price but a boundary, and the page treats it that way: it flags the weight instead of silently extending the ladder past its end. One step past 3.5 oz, the piece is not a letter at all — a flexible one prices as a large envelope (flat) by the ounce, and a thick or rigid one can price as a parcel. The practical consequence is a cliff, not a slope: the difference between 3.5 oz and 3.6 oz is not one more 29-cent step but a different product with different pricing. If your mailing sits near the ceiling, weigh a finished sample — envelope, contents, the lot, on a kitchen scale — before committing to a quantity, because a mailing of a thousand pieces priced as letters that actually ships as flats is a budgeting error multiplied a thousand times.
The whole mailing, added up
The default mailing on this page is 10 letters at $1.36 each plus 4 packages at $9.50 each: $13.60 + $38.00 = $51.60 in total. Change the letter weight to 1 oz and the letters fall to $7.80, giving $45.80 in total; change it to 3.5 oz and the letters rise to $16.50, giving $54.50. The package side never moves with the letter side — per-package price times the number of packages, added to the letter total — which is why the page keeps the two subtotals visible rather than merging them into one number. That separation is what makes the calculator useful for planning: you can see whether the letters or the packages dominate the budget (here the packages do, $38.00 against $13.60), and which side to attack if the total needs to come down. Note also what the package price is: a price you type, per package, from your own label or meter summary. The page deliberately does not ask for a ZIP code or zone for packages, because package pricing depends on service, zone, weight and dimensions in ways a two-number letter ladder cannot capture — the honest input for a package is the price you were actually quoted or charged.
One letter, three prices: retail, metered, commercial
There is no single price to hard-code for a letter, and the page’s defaults illustrate why. The same 1 oz letter cost 78 cents at the retail counter, 74 cents through a meter, and less again on commercial rates, at the July 2025 prices behind the defaults. The gap between retail and metered — four cents on the first ounce — is small on one letter and real on a mailing: on the default’s 10 letters it would be 40 cents on the first ounces alone, before additional ounces, and on a thousand letters it would be $40.00. The page asks for your two numbers instead of hard-coding any of them, and the sources it names are the ones to use: usps.com under Mailing and Shipping Prices, the Postal Explorer, and your own meter tape or label summary, which shows the prices that actually leave your account. One comfort survives every price change: a Forever stamp always covers the first ounce of a standard letter, whatever you paid for it — it is the extra ounces that need topping up, at the current additional-ounce price, whatever that is when you mail.
What this calculator deliberately does not do
Three omissions are stated on the page and worth repeating here, because each one is a place where a careless user could mistake an estimate for a quote. First, it does not verify your rates: if you type last year’s first-ounce price, it will happily compute last year’s postage. The defaults are the July 2025 example rates, and USPS has repriced since calculators like this were built — check before you mail. Second, it does not price flats or parcels by weight and zone: past 3.5 oz it flags the letter rather than pricing the flat, and packages take a typed price rather than a computed one. Third, it does not account for extra services — tracking, insurance, certified mail, return receipt — which are separate purchases on top of postage. Treat the total as the postage budget for the pieces and prices you entered, at the rates you entered, and add services separately from the current USPS price list.
A mailing of a thousand: where the cents become dollars
Per-letter figures look small until they are multiplied. The table below scales this page’s own per-letter prices — at the July 2025 example rates — to a mailing of 1,000 letters, with no packages, so the letter side stands alone.
| Letter weight | Per letter | 1,000 letters |
|---|---|---|
| 1 oz | $0.78 | $780.00 |
| 3 oz | $1.36 | $1,360.00 |
| 3.5 oz | $1.65 | $1,650.00 |
The gap between the first and second rows is $580.00 on a thousand letters — the price of the two extra ounces, 58 cents each, multiplied a thousand times. That is why the weighing advice in the first section matters more the larger the mailing: a mailing that sits at 2.2 oz pays the 3 oz price on every piece, so a thousand-piece mailing at 2.2 oz costs $1,360.00, exactly the same as a thousand pieces at 3 oz. If trimming the contents — a lighter insert, a thinner card — could bring the piece to 2.0 oz exactly, the price would fall to $1.07 per letter (the first ounce plus one extra ounce at the example rates) and the mailing to $1,070.00, saving $290.00. And if it could reach 1 oz, the mailing would cost $780.00, saving $580.00 against the 3 oz price. Weight is the cheapest lever in mailing: it costs nothing to weigh a sample, and every ounce saved is saved on every piece.
The payment method is the second lever, and the page’s own figures size it. At the July 2025 prices, a 1 oz letter cost 78 cents at the retail counter and 74 cents through a meter — four cents on the first ounce. On a thousand 1 oz letters that is $780.00 retail against $740.00 metered, a $40.00 saving for using the meter, before additional ounces are even considered. Commercial rates go lower again, though the page does not quote a commercial first-ounce figure, and this guide does not invent one — the point is the direction, not the exact commercial number. For a one-off letter the method barely matters; for a regular mailing it is a standing discount, and the meter or commercial account pays for itself in the gap between the two columns. The discipline is the same as for the rates themselves: use the prices you actually pay, from your own meter tape or label summary, and let the calculator multiply them honestly.
The practical method for a large mailing follows from both levers. First, finish one complete sample — envelope, contents, the lot — and weigh it on a kitchen scale. Second, weigh ten finished samples and use the heaviest, not the average: USPS bills each piece at its own weight, so the heaviest piece sets the price for the pieces like it, and an average hides the pieces that cross an ounce line. Third, decide the payment method and type its rates, not the retail defaults, if you will meter or send commercially. Fourth, multiply — and check the total against the page before committing to print. A mailing priced after printing is a mailing whose price cannot change; a mailing priced before printing is a mailing whose weight still can.
The July 2025 prices, applied: letters at three weights
First-Class letter pricing from 13 July 2025, with the 3.5-ounce boundary that ends letter pricing.
From 13 July 2025, a First-Class Mail letter costs 78 cents for the first ounce, with each additional ounce at 29 cents. A 1-ounce letter is therefore 78 cents, a 2-ounce letter $1.07, and a 3-ounce letter $1.36. Metered mail (postage printed by an approved meter or online postage system) starts at 74 cents for the first ounce. Those are the figures for ordinary letters: the calculator on this page deliberately prices by the inputs you enter rather than by a built-in rate table, so the figures above are the check against which to test any result, not a substitute for the current price list on usps.com.
The boundary to watch is 3.5 ounces. A letter over 3.5 ounces leaves standard letter pricing behind: it is priced as a large envelope or parcel, and rigid, square or unusually shaped pieces attract nonmachinable surcharges even within the weight limit. Weight is rounded up, never down — a 2.2-ounce letter pays the 3-ounce price — so weighing the whole piece, envelope and contents together, on a kitchen scale is the single most useful habit this page can teach. Anything close to a boundary should be weighed twice.
Retail, metered, and commercial: the same letter, three prices
The service is the same. The price depends on how the postage was bought and in what volume.
Retail postage — stamps and counter purchases — is the highest price for a given piece. Metered postage is a few cents lower per letter, because the meter does the work of printing and accounting for the postage. Commercial postage, bought through an approved online system or a postage provider in volume, can be lower again, with discounts that vary by service, weight and destination. For packages the spread is wider: the July 2025 change raised Priority Mail prices by about 6.3% on average, Ground Advantage by about 7.1% and Parcel Select by about 7.6%, while Priority Mail Express prices did not change, and temporary peak-season adjustments add further variation in the autumn.
The practical consequence is to price the mailing you will actually send, in the channel you will actually use. A thousand-piece mailing priced at retail rates overstates the cost by the whole commercial discount, and a package priced at the July 2025 base rate understates a peak-season mailing by the temporary surcharge. The calculator’s role is to multiply the price you enter by the pieces you enter, honestly, in the service you chose — the price itself must come from the current USPS price list or the postage provider’s quote for the exact service, weight, zone and date.
Frequently asked questions
How is postage for a letter calculated?
Take the first-ounce price, then add the additional-ounce price once for every extra billed ounce, and multiply by the number of letters. Fractions of an ounce bill as whole ounces, so a 3 oz letter at 78 cents for the first ounce and 29 cents for each additional ounce costs $0.78 + 2 × $0.29 = $1.36. This calculator does exactly that, with the rates you enter.
Does USPS round my letter’s weight up or down?
Up — always up. Any fraction of an ounce bills as the next whole ounce, so a letter weighing 2.01 or 2.2 oz pays the 3 oz price, while exactly 2.0 oz pays the 2 oz price. The calculator follows the same rule: it rounds the weight up to the billed ounce before it prices anything.
How much are the first ounce and an extra ounce right now?
The defaults on this page match the USPS retail letter prices that took effect on 13 July 2025: 78 cents for the first ounce and 29 cents for each additional ounce. Prices change, and metered and commercial mailers pay different figures, so check usps.com for the rates that apply to you and type them in — every result on the page follows the rates you enter.
What if my letter weighs more than 3.5 oz?
It stops being priced as a letter. A piece over 3.5 oz that is still flat and flexible moves to large-envelope (flat) pricing, charged by the ounce on a different ladder; a thick or rigid piece may be priced as a parcel instead. This calculator flags any letter weight over 3.5 oz rather than extending letter prices past the limit where USPS itself stops applying them.
Why doesn’t this calculator ask for a ZIP code or zone for packages?
Because honest package pricing needs the service, the weight, the dimensions and the zone together — a single per-package chart with none of those would be invented numbers. Instead, you enter the per-package price you are actually paying, from your shipping label or from usps.com, and the calculator multiplies it by your quantity and adds it to your letters. The arithmetic is exact; the rate is genuinely yours.
Is one Forever stamp enough for a 2 oz letter?
No — a Forever stamp covers the first ounce only. A 2 oz letter also owes one additional-ounce amount, so at the example rates it needs $0.78 + $0.29 = $1.07 of postage. The stamp still counts in full; you simply add the extra 29 cents in stamps or postage, and this calculator shows the shortfall before the letter leaves the house.
Are the rates on this page current?
They are example defaults, not a live price list: the first-ounce price of $0.78 and the additional-ounce price of $0.29 come from the USPS price change of 13 July 2025, when the first ounce rose from 73 to 78 cents and each additional ounce from 28 to 29 cents. USPS reprices its products regularly, so any calculator that hard-codes “the” postage price starts going stale the day it is published. Type the rates you actually pay — from usps.com, the Postal Explorer, or your own meter tape or label summary — and the arithmetic will be current even when the defaults are not.
Why does a 2.2 oz letter cost the same as a 3 oz letter?
Because USPS bills any fraction of an ounce as a whole extra ounce, always rounding up. A 2.2 oz letter bills as 3 oz and costs $1.36 at the page’s example rates — exactly the same as a letter that actually weighs 3 oz. The rounding is never to the nearest: a 2.1 oz letter and a 2.9 oz letter both pay the 3 oz price. Weigh a finished sample before committing to a quantity, because a mailing that sits just over an ounce line pays the higher price on every single piece.
What happens at exactly 3.5 oz, and just past it?
At exactly 3.5 oz the letter still bills on the ladder: the ceiling rounds it to 4 billed ounces, giving $0.78 + 3 × $0.29 = $1.65 at the example rates. At 3.6 oz it is not a letter at all — a flexible piece prices as a large envelope (flat) by the ounce, and a thick or rigid one can price as a parcel. That is why this page flags the weight instead of silently extending the ladder: the difference between 3.5 and 3.6 oz is not one more 29-cent step but a different product with different pricing.
Does one Forever stamp cover my letter?
For the first ounce of a standard letter, yes — always, whatever you paid for the stamp. A Forever stamp covers the first ounce at whatever the current first-ounce price is, which is why it is the one part of postage that never goes stale. It is the extra ounces that need topping up: a 3 oz letter at the example rates needs $1.36 in total, so one Forever stamp plus 58 cents of additional postage covers it, at the current additional-ounce price when you mail.
What is a Forever stamp worth after a price rise?
It is still worth one ounce of First-Class Mail, whatever the current price is. A Forever stamp bought at 73 cents before 13 July 2025 still mails a 1-ounce letter after the rise to 78 cents, with no extra postage needed, and the same applies after any future rise: the stamp’s value follows the current 1-ounce rate. It does not cover additional ounces, nonmachinable surcharges, or other services — a 2-ounce letter needs a Forever stamp plus the additional-ounce postage, however the stamps were bought.
Does USPS deliver mail on Sundays?
Ordinary mail — First-Class letters and most parcels — is delivered Monday to Saturday, with no regular Sunday delivery. Priority Mail Express is delivered on Sundays and holidays in most areas, and some parcels, including Amazon deliveries handled by USPS, are delivered on Sundays in many places. Post offices themselves are generally closed on Sundays, though self-service kiosks in lobbies remain available. If Sunday delivery matters, choose the service that guarantees it rather than assuming a standard service will arrive early.
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