--- title: "OHTO Minimo: The 91 mm Pocket Ballpoint and Refills" canonical: "https://stationerytimes.com/guides/ohto-minimo/" description: "OHTO Minimo mini ballpoint explained: 91 mm long, 3.7 mm thin, 3.1 g aluminum body, R-4C5NP 0.5 mm needle refill, colors, the pencil version, and who it suits." category: "Pens" type: "Ballpoint" published: 2026-10-22 updated: 2026-10-24 author: "Ellis Penhale" publisher: "Stationery Times" sources: 8 products: - name: "OHTO Minimo retractable mini ballpoint pen, 0.5 mm (NBP-505MN)" brand: "OHTO" brand_origin: "Japan" made_in: "Not stated" material: "Aluminum barrel, brass tip cone and knock, steel (SK) clip" price_band: "$$ ($5–20 per pen (multi-packs divided by the count), typical US retail, October 2026)" manufacturer: "OHTO Co., Ltd. (Japan)" model: "NBP-505MN" mpn: "NBP-505MN-PK" gtin: "4971516011193" url: "https://ohto.co.jp/global/products/tl/minimo/" --- # OHTO Minimo: The 91 mm Pocket Ballpoint and Refills > The OHTO Minimo is a tiny retractable ballpoint: OHTO lists it at 91 mm long, 3.7 mm across and 3.1 g, with an aluminum barrel and brass parts. It writes with a 0.5 mm needle-point R-4C5NP refill in low-viscosity oil-based ink, and slips into a wallet, planner loop or notebook spine. - URL: https://stationerytimes.com/guides/ohto-minimo/ - Category: Pens - Author: Ellis Penhale - Published: 2026-10-22 - Updated: 2026-10-24 ![Pink OHTO Minimo mini ballpoint drawn to scale at 91 mm, with an inset of its 0.5 mm needle tip](https://stationerytimes.com/images/raster/ohto-minimo-16x9.png) *The Minimo at 91 mm, drawn to scale: about two-thirds the length of a standard pen.* Original drawing (SVG): . Drawings © 2026 Stationery Times, reusable with credit under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). ## Product facts | Product | Brand | Brand origin | Made in | Material | Released | Price range (typical US retail, October 2026) | |---|---|---|---|---|---|---| | OHTO Minimo retractable mini ballpoint pen, 0.5 mm (NBP-505MN) | OHTO (by OHTO Co., Ltd. (Japan)) | Japan | Not stated | Aluminum barrel, brass tip cone and knock, steel (SK) clip | – | $$: $5–20 per pen (multi-packs divided by the count) | - Made in (OHTO Minimo retractable mini ballpoint pen, 0.5 mm (NBP-505MN)): Not stated. OHTO's English product page and the retailer listings we read (Cult Pens, Yoseka Stationery, Milligram) don't state where the Minimo is made. OHTO is based in Yuki, Japan, but we found no source naming the Minimo's factory. ### OHTO Minimo retractable mini ballpoint pen, 0.5 mm (NBP-505MN) colors - Body colors (4 standard, 0 special edition): Black; Pink; Blue; Silver. - Per OHTO (English) (https://ohto.co.jp/global/products/tl/minimo/), checked 2026-10-24. Colors and item codes per OHTO's English minimo page. Tints were sampled from OHTO's product photos. Shops stock different colors; check the listing. ## Key takeaways - OHTO lists the Minimo (NBP-505MN) at 91 mm (3.6 in) long, 3.7 mm across (5.6 mm at the clip) and 3.1 g. - Its R-4C5NP refill is 67.3 mm long and 2.3 mm thin, with a 0.5 mm tungsten carbide ball in a needle tip and OHTO's low-viscosity soft ink. - OHTO sells it in black, pink, blue and silver; blue was added in Japan on October 31, 2023. - A matching Minimo mechanical pencil (SP-505MN) is 91 mm long and 3.3 mm across and takes 0.5 mm lead. - Cult Pens calls the Minimo the most compact pen it stocks, and it sells in our $$ band ($5–20) in the US. ## What is the OHTO Minimo? **The Minimo is OHTO's mini click ballpoint, built to be carried everywhere rather than to write pages.** OHTO lists the NBP-505MN at 91 mm (3.6 in) long and 3.7 mm across, in an aluminum barrel with a brass tip and knock. It has been around for more than a decade. The Gadgeteer reviewed it in August 2013 and called it one of the thinnest and smallest click pens the author had seen. OHTO sells it in black, pink, blue and silver. ## OHTO Minimo specs | Spec | Value | |---|---| | Maker | OHTO Co., Ltd., Japan | | Model | NBP-505MN | | Type | Retractable ballpoint, low-viscosity oil-based soft ink | | Ball | 0.5 mm tungsten carbide, needle tip | | Length | 91 mm (3.6 in) | | Diameter | 3.7 mm; 5.6 mm at the clip | | Weight | 3.1 g | | Refill | R-4C5NP, 67.3 × 2.3 mm (2.6 × 0.09 in) | | Materials | Aluminum barrel; brass cone and knock; steel clip | | Colors | Black, pink, blue, silver | All figures are from OHTO's English product and refill pages. Yoseka Stationery lists 9.2 cm and 0.5 cm, close to OHTO's numbers. ![OHTO Minimo 91 mm long next to its 67.3 mm R-4C5NP refill and a 136.4 mm OHTO GS01, drawn to scale](https://stationerytimes.com/images/ohto-minimo-size.svg) *The Minimo is two-thirds the length of a full-size GS01 and about a third as thick.* ## Who is the Minimo for? **It's for people who want a real pen on them at all times: in a wallet, a planner loop, a passport cover or a notebook spine.** At 3.1 g you won't notice it, and the clip keeps it in place. It is not a pen for long sessions. Yoseka Stationery says writing an essay with it wouldn't be fun, and the 3.7 mm barrel gives your fingers little to hold. For a fuller grip in a pocket size, look at our [best pocket pens](https://stationerytimes.com/guides/best-pocket-pens/), which include the [Kaweco Sport](https://stationerytimes.com/guides/kaweco-sport/) and the [Fisher Space Pen Bullet](https://stationerytimes.com/guides/fisher-space-pen-bullet/). ## What refill does the Minimo use, and how do you change it? **It takes OHTO's R-4C5NP, a 0.5 mm needle-point refill that OHTO lists for the Minimo by name.** It is 67.3 mm long and 2.3 mm thin, with a stainless steel tube and a tungsten carbide ball. OHTO groups it with its D1 refills and says it follows ISO 12757, the size family used in many multi-pens. Cult Pens sells it as a needlepoint multipen refill. Because it is so small, budget for spares: a mini refill holds less ink than a full-size one. ## Is there a Minimo pencil or other version? **Yes: OHTO also sells a Minimo mechanical pencil, the SP-505MN, at 91 mm long and 3.3 mm across.** It takes 0.5 mm lead and comes in black and pink. In Japan, OHTO added a blue Minimo ballpoint on October 31, 2023 and a pen-holder version in blue and silver on November 1, 2024. OHTO also says the Minimo won the grand prize in a women's promotional products contest at the Premium Incentive Show in 2018. ## How does the Minimo compare with other small pens? **It's the slimmest and lightest of the common pocket pens, with the smallest refill.** | Pen | Length closed | Weight | Refill | |---|---|---|---| | OHTO Minimo | 91 mm (3.6 in) | 3.1 g | R-4C5NP (D1 size) | | [Fisher Space Pen Bullet](https://stationerytimes.com/guides/fisher-space-pen-bullet/) | 96 mm (3.8 in) | about 21 g | PR4 pressurized | | [OHTO GS01](https://stationerytimes.com/guides/ohto-gs01/) (full size) | 136.4 mm (5.4 in) | 17.3 g | PS-107NP (G2) | Fisher figures come from our Fisher guide. Choose the Bullet if you want a sturdier pen that writes in any position, and the Minimo if weight and thickness matter most. ## Where is the OHTO Minimo made? **OHTO doesn't say, and neither do the retailers we checked.** OHTO is a Japanese company with its head office and factory in Yuki, Ibaraki; our [OHTO history](https://stationerytimes.com/stories/ohto-history/) covers the company. ## Frequently asked questions ### How small is the OHTO Minimo? OHTO lists it at 91 mm (3.6 in) long and 3.7 mm across, about as thin as a pencil lead sleeve and short enough to fit a wallet or business-card holder. ### What refill does the OHTO Minimo take? The R-4C5NP, a 0.5 mm needle-point refill 67.3 mm long and 2.3 mm thin. OHTO files it under its D1 refills, the ISO 12757 size used in many multi-pens, and Cult Pens sells it as a needlepoint multipen refill. ### Is the Minimo comfortable for long writing? Not really. At 3.1 g and 3.7 mm thick it is made for quick notes; Yoseka Stationery calls it perfect for a wallet but not much fun for an essay. ### Is there a Minimo pencil? Yes. OHTO's Minimo sharp (SP-505MN) is a 0.5 mm mechanical pencil, 91 mm long and 3.3 mm across, in black and pink. ### Where can you carry an OHTO Minimo? In a wallet, a planner's pen loop, a notebook's spine or a shirt pocket. Its clip is 5.6 mm at the widest point, per OHTO. ### Is the OHTO Minimo made in the USA? No. OHTO is a Japanese company, but none of the pages we read name the country where the Minimo is made. ### Did the Minimo win an award? OHTO says the Minimo won the grand prize in the women's promotional products contest at Japan's Premium Incentive Show, announced September 7, 2018. ## Sources - [OHTO (English): minimo (NBP-505MN colors and JAN codes, 91 × 3.7 mm, max 5.6 mm, 3.1 g, materials, R-4C5NP)](https://ohto.co.jp/global/products/tl/minimo/) - [OHTO (English): minimo sharp (SP-505MN, 91 × 3.3 mm, max 5.2 mm)](https://ohto.co.jp/global/products/tl/minimo-2/) - [OHTO (English): R-4C5NP 0.5 refill (ISO 12757, TC 0.5 mm, 67.3 × 2.3 mm, 1 g, spare for NBP-505MN)](https://ohto.co.jp/global/products/refill/d1-refill/r-4c5np-0-5/) - [OHTO Japan: home page news list (Minimo award September 7, 2018; blue NBP-505MN-BL October 31, 2023; pen-holder type November 1, 2024)](https://ohto.co.jp/) - [Cult Pens: OHTO Minimo Ballpoint Pen (91 mm, 3.68 mm, the most compact pen it stocks)](https://cultpens.com/products/ohto-minimo-ballpoint-pen) - [Yoseka Stationery: OHTO Minimo 0.5 mm Ballpoint Pen (9.2 cm, 0.5 cm)](https://yosekastationery.com/products/ohto-minimo-0-5mm-ballpoint-pen) - [Milligram: OHTO Minimo Ballpoint Pen](https://milligram.com/products/ohto-minimo-ballpoint-pen) - [The Gadgeteer: The OHTO Minimo ballpoint pen could be the world's skinniest clicky pen (August 12, 2013)](https://the-gadgeteer.com/2013/08/12/the-ohto-minimo-ballpoint-pen-could-be-the-worlds-skinniest-clicky-pen)