Copainter Logo
PLANQ&A

AI Support for
Illustration Creation

copainter is an AI tool that assists in the creation of illustrations, manga, and anime.
By combining AI with creativity, it offers a richer creative experience.

Try it for free first

View Plan List
copainterのデモ画面 - タブレットでイラストを描くキャラクターとマスコットキャラクター

Features of copainter

The AI tool copainter streamlines production processes such as inking, undercoating, coloring, backgrounds, and finishing. It supports the creative activities of all creators, from professional artists to hobbyists, and assists in the production of high-quality works.

No high-performance PC or complex software is required to use the tool. Its intuitive web interface allows even those unfamiliar with AI tools to use it easily. copainter is a next-generation production support tool that expands the possibilities for creators and facilitates effortless creation.

Why not utilize illustration generation AIin your production process?

Rough Sketchイラスト
Rough Sketch
Line Artイラスト
Line Art
Undercoatingイラスト
Undercoating
Coloringイラスト
Coloring
Rough Sketchイラスト
Rough Sketch
Line Artイラスト
Line Art
Undercoatingイラスト
Undercoating
Coloringイラスト
Coloring

Examples of Using Illustration AI in Each Process

Line Art/Inking AI: Explore Your Own Style While Refining Line Art

線画の下書き
線画の完成形

[Line Art Function] Fidelity: 0.6, Line Thickness: 0, Stroke Start/End: 0, Auto Prompt Detection from Image

With the line art/inking function, you can create beautiful line art from rough sketches. By adjusting fidelity, you can maintain your unique style while achieving refined expressions. Additionally, prompts can be utilized for detailed style adjustments.

Coloring AI: Color According to the Image of the Work from Undercoating

着彩前の状態
着彩後の完成形

AI Transformation Strength: 0.5, Detail Level: 0.5, Conversion Mode: Normal, Model: Brush Painting

Using the coloring function, natural coloring that aligns with the image of the work is possible from line art and undercoating. It supports various expressions such as brush painting, anime painting, and watercolor painting. Outputs are divided into layers, making post-processing editing easy. High-quality coloring can be efficiently achieved, even in professional production settings.

Image Transformation AI: For Reference Materials and Enhancing Works

変換前の画像
変換後の画像 - 赤髪・青髪

[Top image] Original image[Left image] Original image

[Bottom image: Top] Model: faithful model, Prompt: blue hair, blue eyes, red hoodie, AI variation strength: 1, Faithfulness: 0.7, Fixed seed[Right image: Top] Model: faithful model, Prompt: blue hair, blue eyes, red hoodie, AI variation strength: 1, Faithfulness: 0.7, Fixed seed

[Bottom image: Bottom] Model: faithful model, Prompt: blue hair, blue eyes, red hoodie, Match input image, AI variation strength: 1, Faithfulness: 0.7, Fixed seed[Right image: Bottom] Model: faithful model, Prompt: blue hair, blue eyes, red hoodie, Match input image, AI variation strength: 1, Faithfulness: 0.7, Fixed seed

The image transformation function allows you to easily generate various illustration variations. You can expand your creative ideas by adjusting character expressions, poses, outfits, adding backgrounds, and more. By adjusting prompts and selecting transformation or creative models, it supports the creation of works in a wide range of styles.

Try it for free first

Creating Background Images

写真から線画への変換例:神社の鳥居とモダンな都市の風景

Creating Background Images

Photo Background Transformation AI + Coloring AI

By using the photo background transformation function, you can easily create background materials suitable for illustrations or manga from landscape photos with AI. It allows you to maintain the composition and atmosphere of the photo while expressing backgrounds that match the style of your work. Additionally, applying the coloring function to the generated background achieves a cohesive finish.

Creating Materials from 3D Models

3Dモデルからの変換例:カラー、線画、グレースケール、異なる配色の比較

Creating Materials from 3D Models

Inking AI + Coloring AI

You can generate illustrations from 3D models, efficiently creating designs for character accessories. By converting models created with 3D CG software like VRoid into 2D illustrations, it enhances the versatility of character design and aids in multifaceted considerations for work development. Furthermore, combining the generated illustrations with the coloring function can lead to a highly complete finish.

Enhancing Existing Works

モノクロ漫画のカラー化例:白黒の漫画ページとAIによるカラー化の比較

Enhancing Existing Works

Coloring AI

Coloring monochrome rough sketches, image sketches, or line art can save time. It is particularly effective when remastering past works or during the color expansion of digitization. Even works previously published in monochrome can be easily colorized for broader distribution.

Reducing Workload in Production Settings

アニメーション制作工程の例:キャラクターデザインと作画指示

Reducing Workload in Production Settings

Inking AI

The inking function significantly improves drawing production speed. AI enhances line art quality and reduces the workload of corrections, allowing more time to be allocated to main production and drawing instructions. Additionally, it effectively reduces human inconsistencies in drawing uniformity.

Enterprise Plan

For corporate clients, we offer an Enterprise plan that includes custom AI models capable of producing your preferred art styles or characters.

Enterprise Plan Inquiries

Try it for free first

Introduction to Our AI Illustration Features

線画・ペン入れAIのビフォーアフター - ラフ線から自然な美しい線画への変換例

Lineart & Inking AI

This AI transforms rough sketches into clean lineart. Compared to standard inking tools, the lines are smoother and more natural. It can also automatically adjust line thickness and opacity to match the artist’s style. Ideal for streamlining the inking process, helping you move faster and more efficiently to the next stage. Supports a wide variety of styles, from casual submissions to professional customization. Suitable for both professional illustration and hobby sketches.

下塗りAIのビフォーアフター - 線画からカラー画像への自動彩色例

Undercoloring AI

Generates beautiful base colors from line art and rough coloring. The output is a PSD file with separate layers for each color, making it easy to make adjustments or add details. This significantly reduces the time needed for base coloring and efficiently supports your creative workflow.

陰影AIのビフォーアフター - 異なる光源での陰影効果のデモンストレーション

Shadowing AI

Automatically generates shadows with ease. You can adjust the light source in real-time to modify the shadow direction and appearance. Multiple light sources are supported, enabling a variety of lighting environments and creative shadow expressions.

着彩AIのビフォーアフター - 線画から完成イラストまでの段階的な彩色プロセス

Coloring AI

Once undercoloring is complete, the AI performs detailed coloring. Supports various styles such as flat, anime-style, and watercolor. PSD format output allows editing and adjustments per layer, greatly reducing production time and enabling more focus on enhancing quality.

画像変換AIのビフォーアフター - キャラクターデザインのスタイル変換例

Image-to-Image AI

This AI transforms simple images into various illustration styles with text prompts. It can convert to anime-style, realistic-style, or photographic styles, and can also add backgrounds or change character expressions. Useful both in the production process and for enhancing completed works.

高解像度化AIのビフォーアフター - イラストの解像度向上例

Upscaling AI

Easily enhance the resolution of your illustrations with AI. Supports horizontal/vertical magnification (e.g. 4x, 16x) and speed adjustment for flexible output. Uses illustration-optimized models to upscale without losing line sharpness or color detail. Ideal for use in SNS, posters, and animation production.

写真背景変換AIのビフォーアフター - 被写体を保ったまま背景を調和的に置き換えた例

Photo Background Conversion AI

This AI recognizes and replaces backgrounds in photos automatically. It retains the subject's characteristics while harmonizing the new background, enabling effective and natural background transformations.

Try it for free first

copainter icon image

PLAN

Please choose the best plan

FAQ
Free

For those who want to try it first

$ 0.00Month
3 tickets/month
Get 10 free tickets upon first registration!
  • 3 tickets each month
  • Basic features of copainter
  • No additional ticket purchase available
Light

For those who want an easy and affordable trial

$ 6.00Month
50 tickets/month
  • 50 tickets each month
  • Basic features of copainter
  • Additional ticket purchase available

*Limited to general users and small businesses (annual sales less than 10 million yen in the most recent year).

You need to log in to subscribe
Popular
Basic

For individuals who regularly use the service

$ 18.00Month
300 tickets/month
  • 300 tickets each month
  • Basic features of copainter
  • Additional ticket purchase available

*Limited to general users and small businesses (annual sales less than 10 million yen in the most recent year).

You need to log in to subscribe
Pro+

For those who want to use it extensively

$ 120Month
Unlimited
  • Unlimited usage
  • Basic features of copainter

This plan is also available to corporate customers with annual sales of 10 million yen or more in the most recent year.

You need to log in to subscribe
Enterprise

For corporate customers

Custom
Unlimited
  • Unlimited usage
  • Basic features of copainter
  • Development of a dedicated model for your company (upon consultation)

Contact us

Feature Comparison by Plan

機能FreeLightBasicPro+Enterprise
Monthly Ticket Allocation3 tickets/month50 tickets/month300 tickets/monthUnlimitedUnlimited
Additional Ticket Purchase×○○--
Users (Number of users available per account)1 user1 user1 user1 userMultiple users

※Ticket validity: 60 days for all plans.

※Ticket allocation timing: Tickets are provided monthly on the same day as your plan registration date for all plans.

※The Free plan can be used free of charge every month.

※For paid plans, the contract automatically renews unless you stop the automatic renewal.

※Paid plans can be cancelled at any time. If you cancel before the renewal date, the next debit will not occur.

※If you cancel a paid plan, you cannot re-register for the same plan until its term ends.

※Even after changing or canceling a plan, tickets can still be used if they remain within their validity period.

※You can upgrade, downgrade, or cancel at any time during the month.

※Prices include tax.

FAQ About AI Illustration Generation

AI Illustration & Useful Info

About AI Illustration Generation

AI illustration generation uses the latest deep learning technology to create images. Compared to traditional manual creation, it drastically speeds up idea realization and enhances creative output. Incorporating this tech into your workflow shortens production time significantly, allowing more focus on creativity and fine-tuning. AI suggestions can also inspire new forms of expression and improve originality and quality.

Comparison with Traditional Production Processes

Traditional workflows required significant time and effort at every stage—from sketch to completion. With tools like Copainter, automatic inking and efficient coloring processes dramatically reduce production time, letting creators devote more time to creative tasks.

Features and Selection Criteria for AI Tools

Key criteria for choosing AI illustration tools include output quality, ease of use, and pricing. Especially for output quality, evaluate technical aspects such as line accuracy, naturalness of coloring, and resolution. Intuitive UI, rich features, and solid support are also important for long-term use.

Benefits and Challenges in Business Use

In business, AI illustration tools offer clear benefits such as reduced labor costs and consistent quality. However, challenges like onboarding and workflow restructuring must be addressed. For large organizations, a phased approach to integration is recommended.

Rights and Considerations for Commercial Use

When using AI illustration tools commercially, it's essential to understand copyright and terms of use. Generated images must comply with each service’s terms. Avoid mimicking others’ works or generating inappropriate content. Also, ensure quality control and consistent expression across outputs.

Try it for free first

Operating Company

RADIUS5

Since its founding in 2015, Radius5 Inc. has been a pioneer in the creative AI field. From around 2018, we began developing AI support tools for creators and have been offering 'copainter,' a tool specializing in illustration and manga production.

Company Name:Radius5 Inc.

Representative:Daisuke Urushibara

Capital:10 million yen

Established:September 2015

Location:1-29-1 Takadanobaba, Shinjuku-ku, Tokyo

Business Description:Providing web services related to creative activities

Company Website
Copainter Logo

Services

  • Pricing Plans
  • Enterprise

Support

  • FAQ
  • Terms of Service
  • Privacy Policy
  • Act on specified commercial transactions

Contact

  • Contact

© 2025 copainter. All rights reserved.