◆ Open annotation platform

Label smarter,
ship better models

Stop wrestling with annotation tools. LabelFlow gives your team a fast, focused workspace — from image upload to export-ready datasets.

Start annotating free → Sign in
4+annotation types
5export formats
∞projects
▶ Three steps to a trained model

From raw images to
export-ready dataset

No setup marathons. No specialist knowledge required. Just a clean workflow that gets out of your way.

01
↑

Upload your images

Drag in a folder, bulk-paste URLs, or use the REST API. Any format, any size. Images land in your project instantly.

JPG PNG WebP Bulk upload
→
02
✏

Annotate with your team

Assign roles, draw bounding boxes or polygons, add classification labels. Reviewers check, annotators fix. No chaos.

BBox Polygon Classification Multi-user
→
03
↓

Export & train

One click. Pick your format — COCO, YOLO, VOC, CSV — and download a dataset your training script can consume immediately.

COCO JSON YOLO TXT Pascal VOC CSV
◆ THE WORKSPACE

A focused annotation canvas.
No clutter. No learning curve.

Everything your annotators need is one click away. Everything they don’t need is hidden.

▣
□
◈
↑
⬡ ⬔ ✶
dog_025.jpg
+ −
dog · 0.97
leash · 0.84
ball · 0.91
LABELS
dog 0.97
leash 0.84
ball 0.91
PROGRESS
Annotated47 / 60
Reviewed31 / 47
⚡ Keyboard shortcuts for every tool
👥 Live team progress tracking
◎ Polygon & bbox in one canvas

Built for the whole pipeline

Every tool your annotation workflow actually needs — nothing it doesn’t

⬡

Pixel-accurate tools

Bounding boxes, polygons, and classification labels. Fast keyboard shortcuts, no lag, no frustration.

◈

Role-based teams

Admins, annotators, reviewers — assign access per project. No accidental overwrites, no chaos.

◎

Project workspaces

Keep datasets, teams, and labels neatly separated. Switch context without losing your place.

⬕

One-click export

COCO JSON, Pascal VOC, YOLO TXT, CSV — export exactly what your training script expects.

⬔

REST API

Automate uploads, trigger exports, query annotation status. Fits any MLOps pipeline.

◉

Smart image management

Batch upload folders, tag images, filter by status. Find what you need in seconds.

◆ Use cases

Built for people who
actually ship models

Whether you’re a solo researcher or coordinating a 20-person annotation team.

🧪

ML Researchers

Build clean, reproducible training datasets fast. Version your label sets, export in any format, and spend less time on tooling.

  • ✓ Polygon & bbox annotation
  • ✓ COCO / YOLO / VOC export
  • ✓ REST API for automation
Most common
👥

Annotation Teams

Coordinate dozens of annotators across multiple projects without the spreadsheet chaos. Roles, reviews, and progress in one place.

  • ✓ Admin / Annotator / Reviewer roles
  • ✓ Per-project access control
  • ✓ Real-time progress tracking
🚀

Startups & Indie Builders

Free, self-hosted, no vendor lock-in. Your data stays yours. Start annotating in minutes, scale when you need to.

  • ✓ Unlimited projects, free
  • ✓ No credit card required
  • ✓ Own your data completely

Works with your stack

All major ML training formats — out of the box

COCO JSON
Pascal VOC XML
YOLO TXT
CSV
JSON

Who built this

A small team that got tired of bad annotation tools and decided to fix it

MM
Martynas Matutis
Martynas Matutis
Tech Lead / DevOps
Full‑stack architect with deep expertise in Django and real‑time systems. Built the core annotation engine and leads technical direction.
VG
Viltė Gluoksnytė
Viltė Gluoksnytė
Scrum Master / QA
Ensures smooth delivery through agile practices and rigorous testing. Manages the backlog and keeps the team aligned on quality.
DM
Deimantė Mišeikytė
Deimantė Mišeikytė
Senior Python / Web Developer
Specialises in backend APIs, database optimisation, and frontend integration. Crafts robust, scalable features that power the platform.
ED
Erika Demenytė
Erika Demenytė
Junior Web Developer / UI‑UX Designer
Creates intuitive, accessible interfaces and assists with frontend development. Focuses on user experience and visual consistency.

Ready when you are

Free account, unlimited projects. No credit card. No nonsense.

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