How Many Stamps Do I Need?
📬 Quick Answer: A standard 1 oz letter needs 1 Forever Stamp ($0.73)
Need exact pricing for packages or international mail? Use the calculator below ↓
⚡ Popular Calculations (click to auto-fill)
USPS Postage Calculator
Calculate exactly how many stamps you need and total postage costs with current USPS rates
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Your Postage Calculation
📦 Shipping Details
💡 Quick Shipping Tips
Measure Accurately
Use a kitchen scale for precise weight measurements. Round up to the nearest ounce for safety.
Save Money
Use forever stamps for letters up to 1 oz. They're valid even if rates increase later.
Faster Delivery
Priority Mail Express guarantees overnight delivery to most locations by 10:30 AM or 3 PM.
📊 Compare All USPS Services
Find the best shipping option for your needs and budget
USPS Ground Advantage
Priority Mail
Priority Mail Express
📋 Detailed Comparison
| Feature | Ground Advantage | Priority Mail | Priority Express |
|---|---|---|---|
| Delivery Time | 2-5 business days | 1-3 business days | Overnight |
| Tracking | ✅ Free | ✅ Free | ✅ Free |
| Insurance (included) | Up to $100 | Up to $50 | Up to $100 |
| Free Packaging | ❌ No | ✅ Yes | ✅ Yes |
| Money-back Guarantee | ❌ No | ❌ No | ✅ Yes |
| Weekend Delivery | ❌ No | ❌ No | ✅ Available |
💰 Your Potential Savings
See detailed comparison of all USPS shipping options
📏 Package Size Visualizer
Understand USPS size limits and optimize your packaging
📦 Package Visualization
📐 Size Comparison
📏 Enter Your Dimensions
✅ USPS Requirements
💡 Packaging Tips
💰 Cost Impact
Live USPS Rates
Current postage rates updated in real-time from official USPS APIs
Domestic Rates
Within the United States
International Rates
To Canada & Worldwide
About These Rates
Rates are fetched directly from USPS APIs and updated every 5 minutes
Rates shown for 1 lb package (6" × 4" × 2") from ZIP 90210 to 10001
Standard retail rates before any commercial discounts
Frequently Asked Questions
Quick answers to common USPS shipping questions
For a standard letter (up to 1 oz), you need 1 Forever Stamp ($0.73 in 2025). Each additional ounce costs $0.24. Large envelopes start at $1.50.
A Forever Stamp is currently worth $0.73 (as of January 2025). They can always be used to mail a 1 oz first-class letter, regardless of future rate increases.
Use our calculator above! Enter your package weight, select "Package" as the mail type, and choose your delivery speed. We'll show you exact USPS rates and how many stamps you need.
Yes! You can combine multiple Forever Stamps to cover the postage cost. Our calculator shows exactly how many stamps you need based on the total cost.
Ground Advantage: 2-5 business days. Priority Mail: 1-3 days. Priority Mail Express: 1-2 days with guaranteed delivery.
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