Phylogenetic Tree Maker
Name the organisms — or paste a Newick string — and the AI works out the branching order, scales the branches and draws a clean tree with support values and a scale bar. No alignment files, no desktop software.
Phylogenetic tree examples
Five ways to draw an evolutionary tree, each shown with a real render — click a card to apply the style, or zoom for the full image.
What is a phylogenetic tree?
A phylogenetic tree is a branching diagram of how a set of organisms — species, populations or genes — descend from common ancestors. Each tip is a taxon, each internal node is the most recent common ancestor of everything beyond it, and the branches between them are lineages. What separates it from a plain cladogram is that here branch length is a quantity: on a phylogram it is proportional to the amount of evolutionary change along that lineage, on a chronogram it is elapsed time, and the scale bar tells you which one you are reading.
Most published trees carry two more things. A support value at each node — a bootstrap percentage or a Bayesian posterior probability — says how strongly the data back that particular grouping, and an outgroup roots the tree so the direction of descent is defined. This phylogenetic tree maker produces the figure: describe the group in plain words, paste a Newick string, or give your own divergence times, and the AI resolves the topology and draws it ready for a lecture slide, a thesis or a paper.
Key facts
- Branch length only carries meaning if the figure has a scale bar — without one, the tree is stating branching order and nothing more.
- A node is a hypothesised common ancestor, not a fossil; it usually has no name and no specimen behind it.
- A support value at a node — bootstrap percentage or Bayesian posterior probability — describes confidence in that grouping, not the age of it.
- The root is placed by an outgroup. An unrooted tree shows the same relationships with no direction of descent.
- Two tips printed next to each other can be distant relatives: relatedness is read through nodes, never across the page.
How does the phylogenetic tree maker work?
Describe the group
Name the species, paste a Newick string with branch lengths, give your divergence times, or just name the group — "the great apes". The AI works out the branching order and how far each lineage runs, using the accepted phylogeny when you have not specified one.
Pick a tree style
A publication phylogram with branches to scale and support values at the nodes, a time-calibrated tree over an axis in millions of years, shaded clade blocks for a review figure, illustrated tips, or a whiteboard sketch.
Refine in the workspace
The tree opens in your workspace where you can edit regions, adjust labels, upscale and export in high resolution for slides, posters, theses or papers.
The parts of a phylogenetic tree
A published tree carries a great deal more than its branching order, and most of what it adds is easy to skim past. These are the parts that hold that extra information — worth checking whenever you read one, and the ones the generator can label for you:
Branch length
The horizontal extent of a lineage — the quantity a cladogram leaves out.
Scale bar
What one unit of branch length means, in substitutions per site.
Support value
Bootstrap or posterior at a node — how well the data back that split.
Node age
On a time-calibrated tree, where a node falls on the axis in millions of years.
Outgroup
A taxon outside the group of interest; without one the tree has no root and states no direction.
Tip alignment
Tips level with one another, or each stopping at its own depth — the first clue to which kind of tree you are holding.
Sister groups
The two lineages leaving one node; each is the other's closest relative on the tree.
Topology
The branching skeleton — root, nodes, tips and clades — which this shares with every cladogram.
Only the horizontal axis carries information. The vertical order of the tips is a drawing convention: the branches at any node can be rotated freely, and one tree can be drawn rectangular, slanted or circular without changing a single relationship it states.
Root, nodes, tips and clades mean the same thing on every tree, cladograms included, so this page does not redefine them. That vocabulary is set out in full here: Cladogram Maker
How to read a phylogenetic tree without misreading it
Almost every mistake with these diagrams comes from reading something into the drawing that the tree does not say. Three worth naming:
Distance is measured along the branches, not down the page
Two tips printed next to each other can be distant relatives. Relatedness is where the lineages meet — the taxa sharing the most recent common ancestor are the closest — and on a phylogram, evolutionary distance is the total branch length between two tips, never the gap between their rows.
The longest branch is not the most advanced
Every living tip has had exactly the same amount of time since the root. A long branch means that lineage accumulated more change, usually because it evolves quickly or split off early — not that it is more complex, more successful or more modern.
A node without support is not a settled relationship
A bootstrap of 55 says the data barely prefer that grouping over the alternatives. A tree printed with low support values, or none at all, is stating a hypothesis — the parts you can lean on are the well-supported ones.
Where are phylogenetic trees used?
Papers, theses & reviews
Clean phylograms with exact taxon names, support values and a scale bar for a background section, a review or a systematics panel — without preparing a data file or opening tree-drawing software.
Lectures & science communication
Time-calibrated trees and illustrated tips are what a slide or an explainer needs — the kind of figure phylogenetics software will not draw and an illustrator has to be commissioned for.
Evolution units, revision notes and lab reports
Trees for evolution units, revision notes and lab reports: name the group and get a diagram that places roots, nodes, clades and the outgroup correctly, or a whiteboard version for the lesson itself.
Phylogram, chronogram and unrooted tree — telling them apart
Look at the scale bar first. If it is labelled in substitutions per site you are reading a phylogram, if it is labelled in years or millions of years you are reading a chronogram, and if there is no scale bar and no root the tree is unrooted and states relationships only. A cladogram is the fourth case: flush tips, no scale bar, branching order alone.
| Phylogram | Chronogram | Unrooted tree | |
|---|---|---|---|
| Scale bar reads | Substitutions per site | Years or millions of years | Usually substitutions per site |
| Branch length is | Amount of evolutionary change | Elapsed time | Amount of change |
| Has a root | Yes, from an outgroup | Yes | No |
| Tips line up | No | Yes, at the present | No |
| Can you read divergence dates | No | Yes | No |
| Typical input | Aligned sequences plus a model | Sequences plus fossil calibrations | Aligned sequences |
| Direction of descent shown | Yes | Yes | No |
An unrooted tree is not an unfinished tree. It is the honest output when the data cannot say where the root belongs; adding a root without an outgroup invents a claim the analysis did not make.
Common questions about phylogenetic trees
How does the AI phylogenetic tree generator work?
You describe the group in plain language. The AI first works out the topology — which taxa form each clade, how far each lineage runs, and what value sits at each node — then draws the tree with your exact taxon names at the tips. Give it just a group name and it uses the currently accepted phylogeny with published branch lengths; give it a tree of your own and it follows that instead.
Can it read Newick format?
Yes. Paste a Newick string and the topology is drawn exactly as written, with its branch lengths and any support values carried through unchanged. If you do not have a file, writing the grouping out in words works just as well — "human and chimp together, then gorilla, then orangutan".
Can I make a time-calibrated tree with divergence times?
Yes — pick the Time-calibrated tree style. Give the ages you want at each node, or simply name the group and the AI uses published divergence estimates. The figure gets a horizontal axis in millions of years with the node ages marked along it, and every tip reaching the present.
Is this a phylogenetics package? Can I load an alignment or compute bootstrap values?
No — this makes tree *figures* for papers, teaching, slides and articles, not phylogenetic inference. If you need to estimate a tree from sequence data, use MEGA, RAxML, IQ-TREE, MrBayes or iTOL. Support values you supply are drawn exactly as given; ones you do not supply are plausible published figures, not a calculation on your data.
What is the difference between a phylogenetic tree and a cladogram?
A cladogram shows branching order alone — its branch lengths are arbitrary. A phylogram scales branch length to the amount of evolutionary change and a chronogram scales it to time. All three are phylogenetic trees, so pick by what you need to say: if only the relationships matter, the cladogram maker draws the simpler figure.
Is the phylogenetic tree maker free? Can I use the trees commercially?
You can generate trees on the free plan (with a watermark on exports). Paid plans remove the watermark and unlock every model and high-resolution export, and you can use your figures in courses, publications and commercial material.
How do you read a phylogenetic tree?
Read relatedness through the nodes, not across the tips. Two taxa are close relatives if the node joining them sits near the tips, and distant relatives if you must travel toward the root to connect them — no matter how near each other they are printed. Then check the scale bar to learn what, if anything, the branch lengths mean, and the node labels to see how well supported each grouping is.
What does the scale bar on a phylogenetic tree mean?
It tells you the unit of branch length, and it is the first thing to look at. A bar labelled something like 0.05 means five substitutions per hundred sites of sequence across that length of branch. A bar labelled in millions of years means the tree is time-calibrated. If the figure has no scale bar, treat the branch lengths as meaningless.
What is an outgroup on a phylogenetic tree?
The outgroup is a taxon known to sit outside the group being studied, included specifically so the tree can be rooted. It identifies which character states are ancestral, which fixes the direction of descent for everything else. Choose one too distant and the rooting becomes unstable; choose one inside the group and the tree is rooted wrongly.
What do bootstrap values mean?
A bootstrap value is the percentage of resampled datasets that recovered that same clade — 95 means the grouping appeared in 95 of 100 replicates. It measures how consistently the data support the grouping, not how old it is and not whether it is true. Values above about 70 are usually reported as reasonable support; low values mark branches worth treating as unresolved.
What is the difference between a node and a clade?
A node is a single branching point: the most recent common ancestor of everything beyond it. A clade is that node plus every one of its descendants. So a node is a point on the tree and a clade is the whole group hanging from it — naming a clade means pointing at a node.
How do I make a phylogenetic tree?
For a figure, describe the group in plain words and the currently accepted phylogeny is drawn, or paste a Newick string from your own analysis and it is rendered as-is. For research, the tree itself comes from sequence data: align the sequences, choose a substitution model, infer the tree with maximum likelihood or Bayesian inference, and bring the resulting Newick here to draw it.
What is the tree of life?
The tree of life is the single phylogeny relating all known organisms, rooted near the split between Bacteria, Archaea and Eukarya. Published versions are always summaries: a complete tree would have millions of tips, so any drawable version collapses whole groups into single branches and shows only the level of detail its figure can carry.
Sources
Keep exploring
Our other diagram tools, and the guides behind them.
Draw your first phylogenetic tree
From a list of organisms to a publication-ready tree in about a minute.
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