B6 to B5 Paper Size Converter

📄 What is B6 Paper Size?

B6 is a compact paper size in the ISO 216 B-series. Its dimensions are 125 × 176 mm (4.92 × 6.93 inches), with an area of approximately 0.022 m². B6 is commonly used for postcards, small notebooks, pocket diaries, and compact envelopes. It's also popular for booklets, flyers, and promotional materials that need to be portable and easy to handle. B6 is exactly half the area of B5, making it a convenient size for companion materials and inserts.

Did you know? B6 is the standard size for many Japanese postcards and is widely used in Asia for compact stationery and notebook products.

📏 What is B5 Paper Size?

B5 is a popular paper size in the ISO 216 B-series, with dimensions of 176 × 250 mm (6.93 × 9.84 inches) and an area of approximately 0.044 m². B5 is widely used for books, notebooks, envelopes, and international printing. It's larger than A5 but smaller than A4, making it a versatile medium size. B5 is commonly used in Japan, Korea, and other Asian countries for school notebooks, paperbacks, and office documents. B5 is exactly double the area of B6, making it a natural step up for documents that need more space.

Fact: B5 is the standard size for many academic journals and paperback books in Asia. It's also a popular choice for premium notebooks and planners.

🧮 The Math: How B6 Becomes B5

The ISO 216 B-series is based on the geometric mean between the A-series sizes. Like the A-series, each step down halves the area. B6 → B5 follows the same principle: each side decreases by a factor of 1/√2 ≈ 0.7071.

• Width: 125 mm × √2 ≈ 176.8 mm (rounds to 176 mm)
• Height: 176 mm × √2 ≈ 248.9 mm (rounds to 250 mm)
• Area: 0.022 m² × 2 = 0.044 m²

Formula: 2 B6 sheets = 1 B5 (in area). To convert from B6 to B5, divide the number of B6 sheets by 2. To convert from B5 to B6, multiply by 2.

📊 Quick Conversion Table: B6 to B5

🖨️ Real‑World Examples: B6 to B5 in Action

• 📚 Notebook Design: B6 pocket notebooks are popular for on-the-go note-taking. When you need to expand to B5, this converter tells you exactly how many B6 pages fit into your B5 layout.
• ✉️ Envelope & Stationery: B6 is a common envelope size for invitations and greeting cards. B5 envelopes are used for larger documents and booklets. Converting between them ensures proper fit and professional presentation.
• 📖 Book Publishing: Many paperback books use B5 for the interior pages, with B6 used for promotional bookmarks and inserts. Understanding the scaling helps with layout planning.
• 🎨 Art & Sketchbooks: Artists often use B6 for quick sketches and B5 for more detailed work. This converter helps plan multi-page sketchbook layouts.
• 📬 Direct Mail Marketing: B6 postcards and B5 mailers are common in direct mail campaigns. Converting between sizes helps maintain consistent branding across different formats.

💡 Professional Tips for B6 to B5 Scaling

❓ Frequently Asked Questions (B6 to B5)

📈 Why Accurate B6‑to‑B5 Conversion Matters

Accurate scaling between B6 and B5 is essential for professional design, printing, and document management. Whether you're designing a notebook, preparing a direct mail campaign, or planning a book layout, this tool ensures your documents fit perfectly every time. Inaccurate scaling can lead to wasted paper, misaligned designs, and costly reprints. With the exact ratio of 2:1, planning your B5 prints from B6 documents becomes precise and predictable.

🌐 Global Standards & Professional Usage

The B‑series (ISO 216) is used alongside the A-series, primarily in Asia, Europe, and Australia. B5 and B6 are particularly popular in Japan, Korea, China, and other Asian countries for books, notebooks, and stationery. This tool supports professional paper size conversions for users worldwide who need to work with B-series formats.

📐 The Full B‑Series Hierarchy

• B0 = 1000 × 1414 mm (1.414 m²) – large posters, banners
• B1 = 707 × 1000 mm (0.707 m²) – display posters
• B2 = 500 × 707 mm (0.354 m²) – medium posters
• B3 = 353 × 500 mm (0.177 m²) – small posters, art prints
• B4 = 250 × 353 mm (0.088 m²) – magazines, notebooks
• B5 = 176 × 250 mm (0.044 m²) – books, notebooks, envelopes
• B6 = 125 × 176 mm (0.022 m²) – postcards, pocket notebooks
• B7 = 88 × 125 mm (0.011 m²) – compact notes, tags
• B8 = 62 × 88 mm (0.0055 m²) – small labels, price tags
• B9 = 44 × 62 mm (0.0027 m²) – mini labels
• B10 = 31 × 44 mm (0.0014 m²) – tiny labels

Each step up doubles the area, making the system intuitive and easy to scale. B6 to B5 is a natural step that maintains the √2:1 aspect ratio.

📊 Comparison: B6 vs B5 at a Glance

🔗 Explore More Paper & Print Tools

Check out our other converters: B5 to B6, B5 to B4, B4 to B5, A4 to A0, A1 to A2, A2 to A1, A3 to A2, A4 to A3, PX to MM, and DPI Calculator. All designed to make your print and design workflows smoother.