Compass and tangent arcs
Open a radius, snap to tangents, equal radii and φ. Double arcs, flows and corner curves join tangentially — no kinks unless you want them.
A construction desk for logos
Every curve has a circle behind it.
D-Line builds logos the way they were drawn for centuries — with compass and straightedge. Draw with circles and tangent arcs, let the geometry be measured, and show your client exactly why the mark looks the way it does.
Runs in your browser. No installation. Works offline.
What it does
Geometry you can see, measure and present
Every tool is built around one idea: a strong mark has an order you can explain.
Construction preview
Select a mark and watch its compass-and-straightedge construction play step by step: every circle derived from the ones before, each with its measured deviation.
Arc analysis and focus
See the circles behind every arc, the curvature comb and the joints where curvature jumps. Hover any part and its whole geometry opens.
Geometric identity
D-Line reads ratios, tangencies, alignments and symmetry — and honestly marks what could be coincidence. Fix small kinks with one click.
Construction video
Turn the construction into an MP4 for Instagram, Reels or your case study: 1080p or 4K, 60 fps, title card, captions and slow zoom.
Presentation plates
Mark, construction, geometry and measurements plates in light or dark — layered SVG for Illustrator and Figma, PNG or PDF.
Colour and gradient assistant
Newton, Itten, screen and perceptual (OKLCH) wheels, harmony rules, curated palettes, WCAG contrast and 60-30-10 distribution.
Typography and lockup
1,900+ Google Fonts, filterable by style and language. Convert to outlines and reshape every letter; size the symbol in multiples of cap height with clear space.
Watch a construction
Your logo, explained in eight seconds
This animation is drawn the same way D-Line draws a construction video: base circle first, every other measure derived from it.
- 01 Base circle
- 02 Concentric φ circle
- 03 Tangent circle
- 04 Definition arcs
- 05 Fill
01 / 05 · Base circle
Our philosophy
The essence of a logo is the dance of arc and curve.
Great marks are rarely free-hand. Behind a speed mark, a shell or an apple there is an invisible order: which curve comes from which circle, where it passes without breaking, which angle repeats.
D-Line removes everything that distracts from that order — colour, stroke weight, effects — until you are ready for them. First you build guide circles and lines; then you draw the definition line out of them.
And we are honest about geometry. With enough circles, some pair will always look like the golden ratio. D-Line writes the deviation next to every relationship and marks what could be chance, so your story to the client is one you can defend.
Draw less. Measure more. Show why.
Construction first
Guides are the skeleton, definition lines are the drawing. Arcs stay true arcs all the way to the exported SVG.
Measured, not assumed
Every relationship is derived and measured. Nothing is labelled φ unless it really is.
Calm tools
Fewer panels, more canvas. Advanced features open when you ask, and get out of the way when you don't.
How it works
From a circle to a presentable mark
01
Build the skeleton
Place circles with the compass and guide lines. Symmetry and the magnet keep everything exact.
02
Trace the mark
Pick segments between intersections, draw tangent arcs and corner curves, fill the areas.
03
Read the geometry
Arc analysis, focus and geometric identity show what you built — and what could be tighter.
04
Tell the story
Play the construction, export the video and the plates, and send the client the why, not just the logo.
Pricing
Free to draw. Pay when you present.
Drawing and learning are never locked. Pro and Ultra add cloud space, AI logo construction from your images, 4K video and clean presentation plates — the things you need when the work goes to a client.
Free
Everything you need to learn and draw
$0/ month
Start free- All drawing tools and lessons
- 10 MB cloud library
- Construction video 1080p (with signature)
- Presentation plates (with signature)
- Forum and gallery
Pro
For designers who present their work
$7/ month
$84 / year · billed yearly
Get Pro- 250 MB cloud library
- 1 AI logo a day from your image
- 4K and 60 fps video, no signature
- Clean presentation plates
- Commercial use licence
- Brand kit
Ultra
For studios and daily heavy use
$15/ month
$180 / year · billed yearly
Get Ultra- Everything in Pro
- 1 GB cloud library
- 10 AI logos a day
- Unlimited brand kits
- Priority support
Early access: every feature is free while we are in beta.
Questions
Do I need to know geometry?
No. The built-in geometry tour explains point, circle, arc, tangent, ratio and symmetry with animations, and the tools snap to the right relationships for you.
Can I use my existing logo?
Yes. Paste any SVG path or a full SVG from Figma or Illustrator. D-Line interprets it in arcs, finds its circles and plays its construction.
What do I export?
SVG with true arcs, PNG, layered presentation plates (SVG, PNG, PDF) and an MP4 construction video up to 4K.
Does it work offline?
Yes. D-Line runs in your browser and can be installed as an app. Your drawings sync to your library when you are back online.
Can I use it commercially?
Logos you design are yours. The Pro and Studio plans include a commercial licence for exports; the free plan adds a small signature to videos and plates.
Can I use the fonts commercially?
Yes. Every font in D-Line comes from Google Fonts and is open source (SIL Open Font License or Apache 2.0). Use it in a client's logo and convert it to outlines — the outlined lettering is your artwork.
Which languages are supported?
D-Line speaks 16 languages: English, Türkçe, Deutsch, Français, Español, Italiano, Português, Nederlands, Polski, Русский, العربية, हिन्दी, Bahasa Indonesia, 简体中文, 日本語 and 한국어.
Draw your next mark with a compass.
Free in your browser. Your first construction video is a few minutes away.
Open D-Line