✉️ C3 Envelope
| Millimeters | 324 × 458 mm |
| Centimeters | 32.4 × 45.8 cm |
| Inches | 12.76 × 18.03 in |
| Points | 918 × 1298 pt |
| Picas | 76.5 × 108.2 pc |
| Pixels (300dpi) | 3827 × 5410 px |
| Pixels (72ppi) | 918 × 1298 px |
✉️ C2 Envelope
| Millimeters | 458 × 648 mm |
| Centimeters | 45.8 × 64.8 cm |
| Inches | 18.03 × 25.51 in |
| Points | 1298 × 1837 pt |
| Picas | 108.2 × 153.1 pc |
| Pixels (300dpi) | 5410 × 7654 px |
| Pixels (72ppi) | 1298 × 1837 px |
Area: 1 C2 = 2 × C3 (double the area). Scaling factor: √2 ≈ 1.4142 per side.
C2 is the go-to size for oversized mail, large catalogs, and premium invitations — this tool helps you scale up from C3.
C2 (area) = C3 × 0.5 · Scale factor = √2 ≈ 1.4142 per side1 C2 sheet has twice the area of 1 C3 sheet.
📏 What is C3 Envelope Size?
C3 is a large envelope size in the ISO 216 C-series. Its dimensions are 324 × 458 mm (12.8 × 18.0 inches), with an area of 0.148 m². C3 is designed to hold A3 paper without folding (A3 is 297 × 420 mm). It's commonly used for professional mail, catalogs, large-format correspondence, and oversized invitations. C3 is exactly half the area of C2, making it a popular choice for large documents and bulk mailings.
📄 What is C2 Envelope Size?
C2 is a very large envelope size in the ISO 216 C-series. Its dimensions are 458 × 648 mm (18.0 × 25.5 inches), with an area of 0.297 m². C2 is designed to hold A2 paper without folding (A2 is 420 × 594 mm). It's commonly used for professional mail, very large catalogs, oversized invitations, and high-impact marketing materials. C2 is exactly double the area of C3, making it the ideal size for very large documents, presentations, and premium mailings.
🧮 The Math: How C3 Becomes C2
The ISO 216 C-series is based on the geometric mean of the A and B-series. Each step up (C3 → C2) doubles the area. The side lengths increase by a factor of √2 ≈ 1.4142.
- Width: 324 mm × √2 ≈ 458 mm
- Height: 458 mm × √2 ≈ 648 mm
- Area: 0.148 m² × 2 = 0.297 m²
Formula: 1 C2 = 2 × C3 (in area). So, if you have 2 C3 envelopes, they can be combined to form 1 C2 envelope (or 1 C3 = 0.5 C2).
📊 Quick Conversion Table: C3 to C2
| C3 Envelopes | C2 Equivalent | Scale factor (side) | Real‑world use |
|---|---|---|---|
| 0.5 C3 | 0.25 C2 | 100% | Small catalog envelope |
| 1 C3 | 0.5 C2 | 141.4% (enlarge) | Standard large envelope |
| 2 C3 | 1 C2 | 200% (double width/height) | Very large catalog envelope |
| 4 C3 | 2 C2 | 282.8% | Bulk mailing bundle |
| 5 C3 | 2.5 C2 | 316.2% | Professional presentation |
| 10 C3 | 5 C2 | 447.2% | Large mailing campaign |
| 25 C3 | 12.5 C2 | 707.1% | Bulk marketing mailer |
| 50 C3 | 25 C2 | 1000% | Large-scale mailing |
✉️ Real‑World Examples: C3 to C2 in Action
- 📦 Professional Mail: C3 is used for large catalogs and oversized invitations. When you need to produce C2 for even larger documents or special deliveries, this converter tells you exactly how many C3 envelopes fit into a C2 layout.
- 💌 Invitations & Announcements: C3 is often used for large invitations and announcements. C2 is used for premium oversized invitations and high-end marketing pieces.
- 📬 Marketing Materials: C3 flyers and catalogs can be designed, and then the same artwork can be scaled to C2 for larger-format mailers or displays.
- 🏢 Office Correspondence: C3 is used for large business letters and official documents. C2 is used for very large presentations and reports.
- 🖨️ Printing & Production: Understanding C3 to C2 conversion is essential for print production, especially when printing multiple envelope sizes from the same sheet.
💡 Professional Tips for C3 to C2 Scaling
🎯 Resolution & Quality
When scaling from C3 to C2, if your original is 300 DPI, the resulting C2 will be ~212 DPI — still acceptable for most posters and displays. For high-quality prints, design at 600 DPI at C3 to get ~424 DPI at C2.
📐 C‑Series vs. A‑Series
C-series envelopes are designed to fit A-series paper. C3 is designed to hold A3 paper (297 × 420 mm) without folding. C2 holds A2 paper (420 × 594 mm) without folding.
💰 Printing & Mailing Efficiency
Printing 2 C3 envelopes from 1 C2 sheet can save paper and costs. Many professional printers support C-series sizes — check your printer settings.
📂 Professional Correspondence
C2 is the ideal size for oversized documents and professional presentations. Use this converter to plan your envelope sizes for special deliveries.
❓ Frequently Asked Questions (C3 to C2)
Q: How many C3 envelopes equal 1 C2?
A: Exactly 2 C3 envelopes make 1 C2 in terms of area. You can fit two C3 envelopes on one C2 sheet.
Q: What is the scaling factor from C3 to C2?
A: Each side is scaled by √2 ≈ 1.4142, meaning you enlarge the width and height by 41.4%.
Q: Can I fit a C3 document into a C2 envelope?
A: Yes, by scaling it up to 141.4% on each dimension. The document will fit, with more white space around it.
Q: What is the difference in area between C3 and C2?
A: C2 has exactly double the area of C3 (0.297 m² vs. 0.148 m²).
Q: Is C3 bigger than C2?
A: No, C2 is larger. C2 is the next size up from C3. 1 C2 = 2 × C3.
Q: What is C3 used for?
A: C3 is used for large catalogs, oversized invitations, professional mail, and large-format correspondence.
Q: What is C2 used for?
A: C2 is used for very large catalogs, premium invitations, professional mail, and oversized correspondence.
Q: Can I print C3 on C2?
A: Yes, by scaling up to 141.4%. Most printers support this scaling. This tool helps you understand the exact ratio.
Q: What is the C‑series used for?
A: C‑series envelopes are designed for flat mail and professional correspondence, holding A‑series paper without folding.
📈 Why Accurate C3‑to‑C2 Conversion Matters
Accurate scaling between C3 and C2 is essential for professional mail, envelope production, and document management. Whether you're preparing a catalog, designing an invitation, or planning a mailing campaign, this tool ensures your envelopes fit perfectly every time. Inaccurate scaling can lead to wasted paper, misaligned designs, and costly reprints.
🌐 Global Standards & Professional Usage
The C‑series (ISO 216) is used alongside the A‑series and B‑series in many countries. C‑series envelopes are specifically designed for flat mail and professional correspondence. C2 and C3 are used for large-format mail and premium correspondence. This tool supports professional envelope size conversions for users worldwide.
📐 The Full C‑Series Hierarchy
- C8 = 64 × 91 mm – small correspondence
- C7 = 91 × 128 mm – small envelopes, invitations
- C6 = 128 × 182 mm – standard envelopes, invitations
- C5 = 182 × 257 mm – medium envelopes, flyers
- C4 = 229 × 324 mm – standard mail, A4 documents, business envelopes
- C3 = 324 × 458 mm – large mail, catalogs, A3 documents
- C2 = 458 × 648 mm – oversized mail, A2 documents
- C1 = 648 × 917 mm – very large mail, posters
- C0 = 917 × 1297 mm – extremely large mail, display
Each step up doubles the area, making the system intuitive and easy to scale.
🔗 Explore More Envelope & Mail Tools
Check out our other converters: C2 to C3, C3 to C4, C4 to C3, C4 to C5, C5 to C4, C5 to C6, C6 to C5, DL to C4, and C4 to DL. All designed to make your print and mail workflows smoother.