Area: 1 B4 = 2 × B5 (B4 is double the area). Scaling factor: √2 ≈ 1.4142 per side.
B5 is the classic notebook size; B4 is used for magazines and larger publications — this tool helps you scale between them for professional design and production.
B4 = B5 × 0.5 · Scale factor = √2 ≈ 1.4142 per side2 B5 sheets combine to make 1 B4 sheet (or 1 B4 = 2 B5).
📏 What is B5 Paper Size?
B5 is a medium-small paper size in the ISO 216 B-series. Its dimensions are 176 × 250 mm (6.9 × 9.8 inches), with an area of 0.044 m². B5 is one of the most popular notebook sizes worldwide, commonly used for journals, diaries, and notepads. It's also used for paperback books, magazines, and professional printing. B5 sits between A5 (148 × 210 mm) and A4 (210 × 297 mm) in size, offering a comfortable writing and reading format. B5 is exactly half the area of B4, making it a natural choice for notebooks and smaller publications.
📄 What is B4 Paper Size?
B4 is a medium-large paper size in the ISO 216 B-series. Its dimensions are 250 × 353 mm (9.8 × 13.9 inches), with an area of 0.088 m². B4 is commonly used for magazines, music scores, and larger publications. It's also popular for official documents, brochures, and professional printing projects. B4 is exactly double the area of B5, making it a natural step up for more detailed content and larger publications.
🧮 The Math: How B5 Becomes B4
The ISO 216 B-series is based on the geometric mean between A-series sizes. Each step up (B5 → B4) doubles the area. The side lengths increase by a factor of √2 ≈ 1.4142.
- Width: 176 mm × √2 ≈ 250 mm
- Height: 250 mm × √2 ≈ 353 mm
- Area: 0.044 m² × 2 = 0.088 m²
Formula: 1 B4 = 2 × B5 (in area). So, if you have 2 B5 sheets, they can be combined to form 1 B4 sheet (or 1 B5 = 0.5 B4).
📊 Quick Conversion Table: B5 to B4
| B5 Sheets | B4 Equivalent | Scale factor (side) | Real‑world use |
|---|---|---|---|
| 0.5 B5 | 0.25 B4 | 100% | Small notebook page |
| 1 B5 | 0.5 B4 | 141.4% (enlarge) | Single notebook spread |
| 2 B5 | 1 B4 | 200% (double width/height) | Magazine page |
| 4 B5 | 2 B4 | 282.8% | Magazine spread |
| 5 B5 | 2.5 B4 | 316.2% | Short publication |
| 10 B5 | 5 B4 | 447.2% | Book chapter |
| 25 B5 | 12.5 B4 | 707.1% | Book volume |
| 50 B5 | 25 B4 | 1000% | Large publication |
🖨️ Real‑World Examples: B5 to B4 in Action
- 📖 Notebook & Journal Production: B5 is the classic notebook size. When you need to produce a B4 publication (like a magazine or larger notebook), this converter tells you exactly how many B5 pages fit into a B4 layout.
- 📚 Magazine & Book Publishing: B4 is commonly used for magazines and music scores. B5 is used for books and notebooks. Understanding the scaling helps with production planning and pagination.
- 🎵 Music Scores: B4 is the standard size for sheet music. B5 is used for smaller music books. Convert between them for consistent formatting.
- 🏛️ Official Documents: B4 is used for official documents and certificates in some countries. B5 is used for internal reports and correspondence.
- 📬 Marketing Materials: B5 flyers are common for professional handouts. B4 offers more space for detailed marketing content and brochures.
💡 Professional Tips for B5 to B4 Scaling
🎯 Resolution & Quality
When scaling from B5 to B4, if your original is 300 DPI, the resulting B4 will be ~212 DPI — still acceptable for most printing. For high-quality magazines and publications, design at 600 DPI at B5 to get ~424 DPI at B4.
📐 Notebook & Publication Design
B5 is the most common notebook size globally. When designing a publication that will be printed in both B5 and B4 formats, use this converter to ensure consistent layout and proportion.
💰 Printing Efficiency
Printing 2 B5 pages from 1 B4 sheet can save paper and costs. Many professional printers support B-series paper sizes — check your printer settings for "scale to fit" options.
📂 Book Production
B5 is a common size for books and notebooks. When planning a publication, understanding how B5 converts to B4 helps with cover design and production planning.
❓ Frequently Asked Questions (B5 to B4)
Q: How many B5 sheets equal 1 B4?
A: Exactly 2 B5 sheets make 1 B4 in terms of area. You can fit two B5 pages on one B4 sheet.
Q: What is the scaling factor from B5 to B4?
A: Each side is scaled by √2 ≈ 1.4142, meaning you enlarge the width and height by 41.4%.
Q: Can I fit a B5 document onto a B4 sheet?
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 B5 and B4?
A: B4 has exactly double the area of B5 (0.088 m² vs. 0.044 m²).
Q: Is B5 bigger than B4?
A: No, B4 is larger. B4 is the next size up from B5. 1 B4 = 2 × B5.
Q: What is B5 used for?
A: B5 is used for notebooks, journals, books, and small publications. It's one of the most common notebook sizes worldwide.
Q: What is B4 used for?
A: B4 is used for magazines, music scores, official documents, and larger publications.
Q: How does B‑series compare to A‑series?
A: B-series sizes are about 1.2× larger than A-series at the same number. For example, B5 (176 × 250 mm) is larger than A5 (148 × 210 mm).
📈 Why Accurate B5‑to‑B4 Conversion Matters
Accurate scaling between B5 and B4 is essential for professional publishing, notebook production, and document management. Whether you're preparing a notebook, designing a magazine, or planning a publication, this tool ensures your documents fit perfectly every time. Inaccurate scaling can lead to wasted paper, misaligned designs, and costly reprints.
🌐 Global Standards & Professional Usage
The B‑series (ISO 216) is used alongside the A‑series in many countries. B5 is one of the most popular notebook sizes globally, and B4 is widely used for magazines and official documents. This tool supports professional paper size conversions for users worldwide.
📐 The Full B‑Series Hierarchy
- B8 = 62 × 88 mm – small notepads, tags
- B7 = 88 × 125 mm – pocket notebooks, passports
- B6 = 125 × 176 mm – small books, notepads
- B5 = 176 × 250 mm – notebooks, journals, books
- B4 = 250 × 353 mm – magazines, music scores, official documents
- B3 = 353 × 500 mm – posters, book signatures
- B2 = 500 × 707 mm – large posters, book covers
- B1 = 707 × 1000 mm – large posters, banners
- B0 = 1000 × 1414 mm – display boards, billboards
Each step up doubles the area, making the system intuitive and easy to scale.
🔗 Explore More Paper & Print Tools
Check out our other converters: B4 to B3, B3 to B2, B2 to B1, A4 to A3, Letter to A4, PX to MM, and DPI Calculator. All designed to make your print and design workflows smoother.