Midjourney sets image shape with the --ar parameter, and the Midjourney aspect ratio you type controls proportions only: --ar 16:9 gives a 1456 × 816 frame in V8.2, not a 1920 × 1080 one. Here, in the Playcut spec library, you get the syntax, the 14:1 and 4:1-HD ceilings per version, the four pixel sizes Midjourney publishes, 1.85:1 written as --ar 37:20, and the same ratios in Playcut, which does not run Midjourney.
What the Midjourney aspect ratio parameter does
Midjourney sets image shape with --ar W:H (or --aspect W:H) at the end of a prompt. Images default to a 1:1 square, the parameter takes whole numbers only, and it controls proportions rather than pixel size, which depends on the model version and on whether the image is SD, HD or upscaled.
The Midjourney facts below come from its Aspect Ratio, Upscalers, Version and Legacy Features help articles (docs.midjourney.com, updated July–September 2026, checked 2026-09-05; Cloudflare-gated, so named rather than linked).
--ar and --aspect: the syntax
Both spellings work: a red bicycle on a pier --ar 16:9 and the same prompt with
--aspect 16:9 give the same frame. Width first, height second, a colon with no spaces; Midjourney reduces the fraction, so
--ar 1920:1080 is stored as 16:9 and --ar 8:10 as 4:5.
Whole numbers only: 139:100, 37:20, 85:110
Decimals are rejected. Midjourney's own examples are --ar 139:100 for 1.39:1 and --ar 85:110 for a US Letter page; by the same arithmetic, 1.85:1 is --ar 37:20 (185:100 reduced) and 2.39:1 is --ar 239:100.
How to set the aspect ratio in Midjourney, step by step
Type your prompt, add a space, then --ar 16:9 (or any W:H) as the last thing in the Imagine bar or Discord message. To match a known size, enter the raw dimensions, such as --ar 1920:1080, and Midjourney reduces them.
On the web Imagine bar and in Discord
On the web, append --ar 4:5 in the Imagine bar and press Enter, or pick the ratio in the settings
panel beside it. In Discord the form is /imagine prompt: your text --ar 4:5, with parameters after
the prompt text and any image URLs.
Converting a pixel size or a print size into --ar
Type the dimensions as the ratio: an 8 × 10 print is --ar 8:10 (stored as 4:5) and a 3440 × 1440 ultrawide is --ar 3440:1440, which becomes 43:18. The aspect ratio calculator does the reduction and the width-for-height arithmetic before you spend a job.
Supported aspect ratio ranges by Midjourney version
Midjourney's Version article caps --ar at 14:1 for V6, V7, V8.1 and V8.2, with a lower 4:1 ceiling when HD is on. Older models were tighter: V4 with --style 4c ran 1:2 to 2:1, V4's 4a and 4b styles accepted only 1:1, 2:3 and 3:2, V3 stopped at 5:2 and the test models at 3:2. The docs also warn that extremely wide or tall ratios are experimental and may produce unpredictable results.
| Model | Dates (Version article) | Max --ar, SD | Max --ar, HD | Where stated |
|---|---|---|---|---|
| V8.2 | Default since July 24, 2026 | 14:1 | 4:1 | Version chart |
| V8.1 | Released April 14, 2026; default June 10 to July 23, 2026 | 14:1 | 4:1 | Version chart |
| V7 | Released April 3, 2025; default June 17, 2025 to June 9, 2026 | 14:1 | No HD mode listed | Version chart |
| V6 / V6.1 | December 20, 2023 / July 30, 2024 | 14:1 (Version chart); "any" (Legacy Features) | No HD mode listed | Both, and they disagree |
| V5, V5.1, V5.2 | 2023 | Any | n/a | Legacy Features |
| Niji 5 | 2023 | Any | n/a | Legacy Features |
| V4, --style 4c | 2022 to 2023 | 1:2 to 2:1 | n/a | Legacy Features |
| V4, --style 4a / 4b | 2022 | 1:1, 2:3, 3:2 only | n/a | Legacy Features |
| Niji 4 | 2022 | 1:2 to 2:1 | n/a | Legacy Features |
| V3 | 2022 | 2:5 to 5:2 | n/a | Legacy Features |
| test / testp | 2022 | 2:3 to 3:2 | n/a | Legacy Features |
V8.1 and V8.2: 14:1 in SD, 4:1 in HD
V8.1 made HD images the default: they render at the upscaled size directly (2048 × 2048 at 1:1) for 1.3 GPU minutes against 0.8 for SD, toggled with --hd and --sd. HD jobs accept ratios up to 4:1, so a 14:1 banner runs in SD and is upscaled afterwards.
Midjourney's V8.1 alpha announcement dates the release to April 14, 2026 and says HD mode, already present in the V8.0 alpha, became 3x faster and 3x cheaper, "so cheap we're making it default".
V7, V6 and the legacy models
The Version chart gives V7 and V6 the same 14:1 ceiling, while the Legacy Features table lists V6 as "any"; the two articles disagree, so treat 14:1 as the enforced figure.
Midjourney aspect ratio cheat sheet: --ar to pixels
At 1:1, Midjourney V8.2 renders 1024 × 1024 in SD and 2048 × 2048 upscaled or in HD. The only other sizes Midjourney publishes are 4:3 at 1232 × 928 (2464 × 1856), 2:3 at 896 × 1344 (1792 × 2688) and 16:9 at 1456 × 816 (2912 × 1632). Other ratios have no published figure, so measure the downloaded file.
| --ar | Decimal | Shape | Midjourney V8.2 SD | V8.2 upscaled / HD | Nearest native Playcut ratio | Nano Banana Pro 1K / 2K / 4K |
|---|---|---|---|---|---|---|
| 1:1 | 1.000 | Square | 1024 × 1024 | 2048 × 2048 | 1:1 | 1024 / 2048 / 4096 square |
| 4:5 | 0.800 | Portrait feed | Not published | Not published | 4:5 | 928 × 1152 / 1856 × 2304 / 3712 × 4608 |
| 3:4 | 0.750 | Portrait | Not published | Not published | 3:4 | 896 × 1200 / 1792 × 2400 / 3584 × 4800 |
| 2:3 | 0.667 | Portrait photo | 896 × 1344 | 1792 × 2688 | 2:3 | 848 × 1264 / 1696 × 2528 / 3392 × 5056 |
| 9:16 | 0.563 | Vertical video | Not published | Not published | 9:16 | 768 × 1376 / 1536 × 2752 / 3072 × 5504 |
| 1:2 | 0.500 | Tall banner | Not published | Not published | 1:2 on Grok Imagine only | Not offered; Grok pixels unpublished |
| 5:4 | 1.250 | Landscape print | Not published | Not published | 5:4 | 1152 × 928 / 2304 × 1856 / 4608 × 3712 |
| 4:3 | 1.333 | Landscape | 1232 × 928 | 2464 × 1856 | 4:3 | 1200 × 896 / 2400 × 1792 / 4800 × 3584 |
| 3:2 | 1.500 | Landscape photo | Not published | Not published | 3:2 | 1264 × 848 / 2528 × 1696 / 5056 × 3392 |
| 16:9 | 1.778 | Widescreen | 1456 × 816 | 2912 × 1632 | 16:9 | 1376 × 768 / 2752 × 1536 / 5504 × 3072 |
| 21:9 | 2.333 | Ultrawide | Not published | Not published | 21:9 | 1584 × 672 / 3168 × 1344 / 6336 × 2688 |
| 2:1 | 2.000 | Panorama | Not published | Not published | 2:1 on Grok Imagine only | Not offered; Grok pixels unpublished |
| 37:20 | 1.850 | Cinema flat | Not published | Not published | None: 16:9, then crop | 2752 × 1488 (1487.6 exact) after cropping the 2K frame |
| 85:110 | 0.773 | US Letter | Not published | Not published | None: 3:4, then crop about 3% of height total (1.5% per edge) from a nominal 3:4 frame; 3.4% on Nano Banana Pro's 896 × 1200 | Not offered |
The Nano Banana Pro column is Playcut's own validation table, not a Google-published spec; only the square values are corroborated by Google's pricing page. Its 16:9 (1376 × 768) is 1.792 and its 21:9 (1584 × 672) is 2.357, both about 1% wider than nominal.
V8.2 SD, upscaled and HD sizes Midjourney publishes
Subtle and Creative upscales both double each dimension and can cost twice the GPU minutes of the original job. HD images generate at the doubled size directly, currently cannot be upscaled further, and their exact dimensions may vary slightly for some ratios.
Why --ar 16:9 comes out 1456 × 816 (91:51, 0.37% off)
All four published dimensions are multiples of 16, consistent with a 16-pixel grid, though the docs do not state that rule. 1456 × 816 reduces to 91:51 (1.784, 0.37% wider than 16:9) and 1232 × 928 to 77:58 (1.328, 0.43% narrower than 4:3). To reach the 1920 × 1080 upload on the YouTube video size sheet, crop about 11 px of width total (10.7 exact, 5–6 per side) from the 2912 × 1632 file and resize.
Common presets: square, portrait, vertical, wide
--ar 1:1 for avatars, --ar 4:5 for portrait feed posts (sizes on the 4:5 aspect ratio sheet), --ar 9:16 for Stories, Reels and Shorts, --ar 16:9 for thumbnails, and --ar 3:2 to match a full-frame sensor (see the 3:2 aspect ratio sheet).
The 1.85:1 cinema ratio in Midjourney
Midjourney rejects decimals, so the 1.85:1 flat theatrical ratio is written --ar 37:20. 1.85:1 debuted at Universal Pictures in May 1953, is one of the two standard US projection ratios alongside 2.39:1, and in digital cinema is delivered as 1998 × 1080 (2K) or 3996 × 2160 (4K) inside the DCI container.
What uses 1.85:1: flat theatrical projection and DCP 1998 × 1080 / 3996 × 2160
Wikipedia's aspect ratio (image) article records the May 1953 Universal debut and the 1.66:1 European counterpart. The DCI 2K container is 2048 × 1080 (1.90:1), cropped to 1998 × 1080 for flat and 2048 × 858 for scope; the 4K flat frame is 3996 × 2160 (easyDCP's flat and scope FAQ).
| 1.85:1 target | Pixels | How you get there |
|---|---|---|
| DCI 2K flat | 1998 × 1080 | Inside the 2048 × 1080 container, 25 px of pillarbox per side |
| DCI 4K flat | 3996 × 2160 | Inside the 4096 × 2160 container, 50 px per side |
| Full-HD width | 1920 × 1038 (1037.8 exact) | Crop a 1920 × 1080 frame by 42 px of height total (21 per edge) |
| Midjourney V8.2, native | Not published | Prompt --ar 37:20, then resize the download to 1998 × 1080 or 3996 × 2160 |
| Midjourney V8.2 SD, if you already have a --ar 16:9 render | 1456 × 787 (787.0 exact) | Crop 3.55% of height total (1.78% per edge) |
| Midjourney V8.2 upscaled / HD, if you already have a --ar 16:9 render | 2912 × 1574 (1574.1 exact) | Same 3.55% total crop at double size |
| Nano Banana Pro 2K, from 16:9 | 2752 × 1488 (1487.6 exact) | Crop 3.15% of height total (1.58% per edge) |
| Nano Banana Pro 4K, from 16:9 | 5504 × 2975 (2975.1 exact) | Same 3.15% total crop; exceeds DCI 4K flat width |
1.85:1 vs 16:9: 4.06% wider, a 3.9% total height crop (1.95% per edge)
1.85 is 4.06% wider than 16:9 (1.778), so cropping a true 16:9 frame to 1.85:1 at the same width removes 3.9% of the height total (1.95% per edge). If you already have a Midjourney --ar 16:9 render (1456 × 816, 1.784) the crop is 3.55% total (1.78% per edge), giving 1456 × 787; a fresh job should use --ar 37:20 instead.
1.85:1 vs 2.39:1 scope and 21:9
1.85:1 is 22.6% narrower than 2.39:1 scope (--ar 239:100), and nominal 21:9 (2.333) is 2.4% narrower than 2.39, close enough to stand in for scope.
Getting the same ratios natively in Playcut
Playcut does not run Midjourney. Its image models are Google's Nano Banana Pro and Nano Banana 2 (1:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9 and 21:9 at 1K, 2K and 4K) and xAI's Grok Imagine (13 ratios plus an auto option at 1K and 2K), so every common Midjourney --ar value except the extreme banners has a native equivalent in the Playcut image generator.
There is no --ar syntax: ratio and tier are dropdowns per generation, and motion prompts go to the video model you pick, such as Veo 3.1 or Seedance 2.0, in the Playcut video generator.
Nano Banana Pro and Nano Banana 2: ten ratios at 1K, 2K and 4K
Both Google models expose the ten ratios above at three tiers, with the pixel sizes in the cheat sheet; Nano Banana 2 adds a 512 tier probed at 1:1, 16:9, 9:16 and 21:9 only. Nano Banana Pro costs 67 credits at 1K and 2K and 84 at 4K; Nano Banana 2 costs 34 and 43, and the pricing page lists each plan's monthly credits. What 2K and 4K mean in pixels is on the 2.5K and 4K resolution sheet.
Grok Imagine: 13 ratios plus an auto option, including 2:1, 19.5:9 and 20:9
On Playcut, Grok Imagine offers auto, 1:1, 16:9, 9:16, 4:3, 3:4, 3:2, 2:3, 2:1, 1:2, 19.5:9, 9:19.5, 20:9 and 9:20 at 1K and 2K, with no 4K tier, for 10 credits per text-to-image render (20 with a reference image). xAI's image generation documentation additionally lists 21:9 and 5:2 and publishes no per-ratio pixel dimensions.
Where the two toolsets differ: 14:1 banners vs 4K output
Midjourney goes wider: 14:1 in SD and 4:1 in HD have no counterpart on a Playcut image model, whose widest setting is 21:9. Playcut goes larger: in Playcut's dimension table, 16:9 reaches 5504 × 3072 at 4K on Nano Banana Pro.
1.85:1 on Playcut: generate 16:9 and crop 3.15%
Playcut has no 1.85:1 preset, so generate 16:9 and crop 3.15% of the height total (1.58% per edge): Nano Banana Pro's 2752 × 1536 becomes 2752 × 1488, and the image resizer does that crop. Midjourney needs no crop: --ar 37:20 renders 1.85:1 natively, and because its pixel size is unpublished you resize the download to 1998 × 1080 or 3996 × 2160.
Common --ar mistakes and how to fix them
Most failed Midjourney aspect ratios come from four things: a decimal in the value (use 37:20, not 1.85:1), a missing space before --ar, the parameter placed mid-prompt, or an HD job asked for a ratio wider than 4:1. A fifth, swapped numbers, turns a 4:5 feed post into a 5:4 landscape.
Decimals, missing spaces and mid-prompt placement
--ar 1.85:1, --ar 16 : 9 and prompt--ar 16:9 typically fail, since the
docs require whole numbers, a colon with no spaces and a space before each parameter. Write
prompt --ar 37:20, keep every
parameter at the tail, and let the Midjourney prompt
generator assemble the block in order.
Hitting the 4:1 HD ceiling
A 14:1 banner refused in HD is not a bug: HD stops at 4:1 in V8.1 and V8.2. Switch the job to SD with --sd, generate at the wide ratio, then run a Subtle or Creative upscale to double it.