Flag Proportion Reference
Every ratio the Flag Proportion & Ratio Calculator and Flag Size for Pole Height Calculatorsupport, in one set of tables — which real flags use each ratio, its finished shape at a sample size, and the flag size it produces at five common flagpole heights.
Ratios, example flags, and shape at a 3-ft hoist
| Ratio | Decimal | Used by | Fly at 3-ft hoist | Area |
|---|---|---|---|---|
| 1:1 | 1 | Switzerland (land flag), Vatican City | 3 ft × 3 ft | 9 sq ft |
| 2:3 | 0.6667 | France, Italy | 3 ft × 4.5 ft | 13.5 sq ft |
| 3:5 | 0.6 | Germany | 3 ft × 5 ft | 15 sq ft |
| 1:2 | 0.5 | United Kingdom | 3 ft × 6 ft | 18 sq ft |
| 9:16 | 0.5625 | No widely-used national flag — comparison ratio only | 3 ft × 5.3333 ft | 16 sq ft |
| 10:19 | 0.5263 | United States, Liberia | 3 ft × 5.7 ft | 17.1 sq ft |
Fly and area are computed for a fixed 3-foot hoist so every ratio can be compared on equal footing. Use the calculator directly for any other hoist or fly.
Recommended flag size by pole height, for each ratio
Each table below applies the standard one-quarter-of-pole-height rule to that ratio, at the pole heights most installers use, and rounds to the closest off-the-shelf fly length.
1:1 — square
| Pole height | Recommended fly | Recommended hoist | Nearest standard fly |
|---|---|---|---|
| 20 ft | 5 ft | 5 ft | 5 ft |
| 25 ft | 6.25 ft | 6.25 ft | 6 ft |
| 30 ft | 7.5 ft | 7.5 ft | 8 ft |
| 40 ft | 10 ft | 10 ft | 10 ft |
| 50 ft | 12.5 ft | 12.5 ft | 12 ft |
2:3 — a widely used proportion
| Pole height | Recommended fly | Recommended hoist | Nearest standard fly |
|---|---|---|---|
| 20 ft | 5 ft | 3.33 ft | 5 ft |
| 25 ft | 6.25 ft | 4.17 ft | 6 ft |
| 30 ft | 7.5 ft | 5 ft | 8 ft |
| 40 ft | 10 ft | 6.67 ft | 10 ft |
| 50 ft | 12.5 ft | 8.33 ft | 12 ft |
3:5 — a widely used proportion
| Pole height | Recommended fly | Recommended hoist | Nearest standard fly |
|---|---|---|---|
| 20 ft | 5 ft | 3 ft | 5 ft |
| 25 ft | 6.25 ft | 3.75 ft | 6 ft |
| 30 ft | 7.5 ft | 4.5 ft | 8 ft |
| 40 ft | 10 ft | 6 ft | 10 ft |
| 50 ft | 12.5 ft | 7.5 ft | 12 ft |
1:2 — long and narrow
| Pole height | Recommended fly | Recommended hoist | Nearest standard fly |
|---|---|---|---|
| 20 ft | 5 ft | 2.5 ft | 5 ft |
| 25 ft | 6.25 ft | 3.13 ft | 6 ft |
| 30 ft | 7.5 ft | 3.75 ft | 8 ft |
| 40 ft | 10 ft | 5 ft | 10 ft |
| 50 ft | 12.5 ft | 6.25 ft | 12 ft |
9:16 — close to a widescreen rectangle
| Pole height | Recommended fly | Recommended hoist | Nearest standard fly |
|---|---|---|---|
| 20 ft | 5 ft | 2.81 ft | 5 ft |
| 25 ft | 6.25 ft | 3.52 ft | 6 ft |
| 30 ft | 7.5 ft | 4.22 ft | 8 ft |
| 40 ft | 10 ft | 5.63 ft | 10 ft |
| 50 ft | 12.5 ft | 7.03 ft | 12 ft |
10:19 — a less common near-2:1 proportion
| Pole height | Recommended fly | Recommended hoist | Nearest standard fly |
|---|---|---|---|
| 20 ft | 5 ft | 2.63 ft | 5 ft |
| 25 ft | 6.25 ft | 3.29 ft | 6 ft |
| 30 ft | 7.5 ft | 3.95 ft | 8 ft |
| 40 ft | 10 ft | 5.26 ft | 10 ft |
| 50 ft | 12.5 ft | 6.58 ft | 12 ft |
How to read this page
The first table answers “what does this ratio look like, and which real flags use it?” — a quick way to compare shapes side by side at the same hoist. The second set of tables answers a different, more practical question: “I have a pole this tall — what size flag, at this ratio, should I actually buy?” Both come from the same underlying arithmetic; this page just arranges it two different ways depending on which question you have.
A ratio’s ideal recommended size always sits at the low end of the quarter-to-third band (see our guide to choosing a flag size for your flagpolefor the full range and the reasoning behind it) — size up toward one-third of the pole height in a sheltered spot where a larger flag is wanted.
Frequently Asked Questions
Where do the numbers in this table come from?
Every dimension here is computed by the same computeFlagDimensions() and recommendFlagSize() logic behind the Flag Proportion & Ratio Calculator and the Flag Size for Pole Height Calculator — this page doesn't maintain a separate hand-typed table, so the two always agree.
Why is the example-flags list empty for the 9:16 ratio?
9:16 is included as a familiar comparison point — it's close to a widescreen video frame — but no widely-used national flag is actually built to it. Rather than guess at an example, the list is left empty.
Does a ratio's example-flags list mean only those flags use it?
No. These are real, verified flags known to use each ratio, not an exhaustive list — plenty of other flags share the same common ratios. Where a country specifies more than one ratio for different uses (Switzerland's square land flag versus its rectangular 2:3 civil ensign at sea, for instance), the table notes the specific context.
How was the pole-height list chosen?
20, 25, 30, 40, and 50 feet span the range most residential and commercial flagpole installers actually sell and install. Our Flag Size for Pole Height Calculator accepts any height if yours falls outside this list.
Educational reference only. Example flags are verified against standard vexillological references; where a country specifies more than one ratio for different uses, only the noted context applies.
Use it with
- Flag Proportion & Ratio Calculator— resolve any hoist or fly at any ratio, not just the sample size shown here.
- Flag Size for Pole Height Calculator— get a recommendation for a pole height that isn’t in the standard list above.
- What a Flag Construction Sheet Actually Shows— the next layer of detail once a ratio is fixed.