✉️ 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 |
✉️ 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 |
Area: 1 C2 = 2 × C3 (C3 is half the area). Scaling factor: 1/√2 ≈ 0.7071 per side.
C3 is used for large catalogs and oversized invitations — this tool helps you scale down from C2 for professional mail and correspondence.
C3 = C2 × 2 · Scale factor = 1/√2 ≈ 0.7071 per side1 C2 envelope splits into exactly 2 C3 envelopes (or 1 C3 = 0.5 C2).
📏 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, 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.
📄 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.
🧮 The Math: How C2 Becomes C3
The ISO 216 C-series is based on the geometric mean of the A and B-series. Each step down (C2 → C3) halves the area. The side lengths decrease by a factor of 1/√2 ≈ 0.7071.
- Width: 458 mm × (1/√2) ≈ 324 mm
- Height: 648 mm × (1/√2) ≈ 458 mm
- Area: 0.297 m² ÷ 2 = 0.148 m²
Formula: 1 C2 = 2 × C3 (in area). So, if you have 1 C2 envelope, you can create 2 C3 envelopes from it (or 1 C3 = 0.5 C2).
📊 Quick Conversion Table: C2 to C3
| C2 Envelopes | C3 Equivalent | Scale factor (side) | Real‑world use |
|---|---|---|---|
| 0.5 C2 | 1 C3 | 100% | Single large catalog envelope |
| 1 C2 | 2 C3 | 70.7% (reduce) | Two large catalog envelopes |
| 2 C2 | 4 C3 | 50% (half width/height) | Four professional envelopes |
| 5 C2 | 10 C3 | 31.6% | Bulk mailing |
| 10 C2 | 20 C3 | 22.4% | Large mailing campaign |
| 25 C2 | 50 C3 | 14.1% | Marketing mailer |
| 50 C2 | 100 C3 | 10% | Large-scale mail |
| 100 C2 | 200 C3 | 7.1% | Massive mailing |
✉️ Real‑World Examples: C2 to C3 in Action
- 📦 Professional Mail: C2 is used for very large catalogs and premium invitations. When you need to produce standard C3 envelopes for regular correspondence, this converter tells you exactly how many C3 envelopes you can create from each C2 envelope.
- 💌 Invitations & Announcements: C2 is often used for premium oversized invitations. C3 is used for standard large invitations and reply envelopes. Understanding the scaling helps with consistent branding.
- 📬 Marketing Materials: C2 flyers and catalogs can be designed, and then the same artwork can be scaled to C3 for smaller-format mailers or handouts.
- 🏢 Office Correspondence: C3 is used for large business letters and official documents. C2 is used for very large presentations and reports. Convert between them for consistent document management.
- 🖨️ Printing & Production: Understanding C2 to C3 conversion is essential for print production, especially when printing multiple envelope sizes from the same sheet.
💡 Professional Tips for C2 to C3 Scaling
🎯 Resolution & Quality
When scaling from C2 to C3, if your original is 300 DPI, the resulting C3 will be ~424 DPI — actually higher quality! This is because you're concentrating the same pixels into a smaller area. For best results, design at 300 DPI at C2 for sharp C3 prints.
📐 C‑Series vs. A‑Series
C-series envelopes are designed to fit A-series paper. C2 is designed to hold A2 paper (420 × 594 mm) without folding. C3 holds A3 paper (297 × 420 mm) without folding. This makes C3 a common choice for large documents.
💰 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 for "scale to fit" options.
📂 Professional Correspondence
C3 is the standard for large business mail, official documents, and professional correspondence. Use this converter to plan your envelope sizes for professional communications.
❓ Frequently Asked Questions (C2 to C3)
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 C2 to C3?
A: Each side is scaled by 1/√2 ≈ 0.7071, meaning you reduce the width and height by 29.3%.
Q: Can I fit a C2 document into a C3 envelope?
A: Yes, by scaling it down to 70.7% on each dimension. The document will fit, but text and details will be smaller.
Q: What is the difference in area between C2 and C3?
A: C2 has exactly double the area of C3 (0.297 m² vs. 0.148 m²).
Q: Is C2 bigger than C3?
A: Yes, C2 is larger. C2 is the next size up from C3. 1 C2 = 2 × C3.
Q: What is C2 used for?
A: C2 is used for very large catalogs, premium invitations, professional mail, and oversized correspondence.
Q: What is C3 used for?
A: C3 is used for large catalogs, oversized invitations, professional mail, and large-format correspondence.
Q: Can I print C2 on C3?
A: Yes, by scaling down to 70.7%. 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 C2‑to‑C3 Conversion Matters
Accurate scaling between C2 and C3 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: C3 to C2, 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.