v3.17.0 — free & open source

Publication figures,
assembled in the browser

Drop in your images. Crop, adjust, annotate, generate AI diagrams, and arrange everything freely — like PowerPoint, but built for science. Export at 600 DPI. Your images never leave your machine — the only thing that ever travels is a prompt, if you choose to use the optional AI generator.

Open FigureLab Source on GitHub
Single HTML file Your images never leave your machine Works offline Exports at 300/600 DPI
7 export formats incl. multi-page PDF
350+ automated tests run on every change
25+ AI scientific subjects to generate
0 dependencies to install

Everything the standard workflow gets wrong — fixed

FigureLab is built around the specific tasks that break down when you chain Fiji, Inkscape, and PowerPoint together.

✦

Freeform canvas — like PowerPoint, built for science

Switch from grid to freeform mode and place anything anywhere: images, shapes, text, AI-generated diagrams. Snap to grid, align edges, distribute evenly — then export the whole canvas at publication DPI.

✂️

Cropping, including at an angle

Crop one panel, batch-crop a whole set to the same window, or cut several named regions out of one image and get a panel from each. Crops are non-destructive and re-editable. A crop can also be tilted — specimens rarely sit square to the camera, so turn the region and the panel still comes out upright — or straightened for you: click two points along an edge, or let the editor find the angle. Lock a ratio, or type the crop in pixels.

🤖

AI diagram & icon generation

Type a prompt — "phage injecting DNA into bacteria" — and generate a BioRender-style scientific cartoon via Gemini or a local Stable Diffusion instance. Remove the white background automatically and place it directly into your figure.

📐

Scale bars that stay correct after cropping

Pixel math is recalculated from the cropped region, not the original image. Auto-detect embedded scale bars in microscope images. Zeiss LSM calibration populates automatically from the VoxelSizeX tag.

🔍

Deep figure audit

Runs 6+ consistency checks: LUT mismatches across panels, inconsistent brightness scaling, missing calibrated scale bars, font size too small for print, and unequal panel sizes in freeform mode.

⚡

Exposure analysis per panel

Detects overexposed panels (mean >210/255), saturated pixels (>5% clipped to white), underexposure, and low contrast — before you export and before a reviewer notices.

📊

Real ROI quantification

Draw a region of interest and get mean intensity, integrated density, min/max, area in px² and µm² (if calibrated), and a line-profile fluorescence plot. Export all measurements as CSV.

🔢

Threshold-based cell counting

Draw an ROI, set a threshold, and count connected objects using flood-fill. Reports object count, foreground area, and µm² when calibrated. No ImageJ required.

🎨

Per-panel adjustments & one-click standardize

Brightness, contrast, gamma, LUTs, black/white point — all per panel. "Match all to this panel" copies every setting to the rest in one click. Histogram normalization auto-stretches or matches to a reference panel.

🗂️

Layout templates

Eight built-in presets for Nature 2×2, Science single-column, Cell 2×3, poster, supplementary 3×3, and more. Save your own templates and share them as JSON files.

📋

Reproducibility log embedded in every PNG

Every PNG export carries tEXt metadata chunks listing every adjustment made — brightness, LUT, crop, normalization, measurements — readable in FIJI, ImageJ, or any EXIF viewer.

✏️

Annotations as a real vector layer

Arrows, rulers, insets, text boxes, ellipses, counters — export as native SVG elements. Edit in Illustrator or Inkscape after export. Crop-to-shape masking with rectangle, ellipse, or circle clip paths.

📄

Multi-page PDF export

Split any grid figure into a multi-page PDF — choose how many rows per page and FigureLab renders each page independently, then assembles a single PDF. Perfect for supplementary figure sets.

📎

TIFF & LSM metadata reader

Reads µm/px calibration directly from TIFF XResolution tags and Zeiss LSM VoxelSizeX blocks. Drop an LSM and your scale bars are calibrated automatically — no manual entry.

🔗

Share settings via link

Encode your entire layout, style, labels, and annotations into a shareable URL. The recipient opens it, drops their own images, and everything is pre-configured. No server. No account. No image data leaves your machine.

⧉

Panel comparison view

Side-by-side comparison of any two panels with synchronized zoom, a live pixel inspector (R/G/B values on hover), per-panel intensity stats, and a difference overlay that quantifies pixel-level variation between channels or conditions.

The story behind FigureLab

There is a Ghanaian adage about a piglet quizzing their mother about why she has such a big snout, only for the mother to respond that it was a matter of time before the piglet would grow to experience such a predicament.

I first encountered this particular predicament at a Texas ASM Branch meeting. I was sitting behind someone working on their laptop, wrestling with ImageJ, Inkscape, and PowerPoint. Cropping a microscopy panel. Dragging it into Inkscape. Trying to align a set of figures. I watched for a few minutes before quietly looking away — privately glad it wasn't me, and privately filing it away as something deeply familiar.

Then it was me.

I had a set of N4 phage infection time-course images that needed to become an eight-panel figure for a manuscript. Calibrated scale bars, annotations to add, brightness adjustments to make. I know Fiji well. I know Inkscape well. I have done this before. And yet two hours in, I was exporting the same TIFF for the fifth time because the panel labels kept rendering at the wrong size, the scale bar math was off when I cropped the image, and the SVG I had painstakingly annotated had lost half its arrows when I reopened it. To add salt to injury, I could not seem to align everything perfectly.

I ended up with a figure I did not like, assembled through a process I hated, using tools I respect but that were simply not designed for this job.

So I did what I sometimes do when I hit a wall in this age of AI: I remembered that you can just build things.

The actual problem with figure assembly

To be clear, Fiji is excellent software. ImageJ has been the backbone of biological image analysis for decades, and the community that built and maintains it deserves enormous credit. Inkscape is a genuinely powerful vector editor. The problem is not that these tools are bad. The problem is that making a publication figure involves a very specific workflow — arrange panels in a grid, apply uniform brightness adjustments, add calibrated scale bars, annotate with arrows and labels, export at 300 or 600 DPI — and none of the tools in the standard academic stack were designed specifically for that workflow. You are constantly leaving one application and entering another, re-importing files, re-doing work.

The hidden cost is not the time per se. It is the fragmentation. Your figure exists simultaneously as a Fiji macro, a set of exported TIFFs, an Inkscape SVG, and a mental model of how they all relate. When something changes — a reviewer wants panel C cropped differently or the scale bar moved — you go back to the beginning of the chain.

The specific failures I kept hitting

Scale bar pixel math that ignored my crop region, giving me a bar that was visually correct but numerically wrong. SVG exports from Fiji that silently dropped my annotations when reopened. PNG files that looked fine on screen but were flagged as 72 DPI by the journal submission portal. A session file that crashed when I had more than four large TIFF files loaded.

These are not exotic edge cases. These are the normal workflow for any microscopy-heavy biology paper.

What I built — and what it became

FigureLab started as a single HTML file with a grid, a crop editor, and a scale bar. You open it in your browser. You drag in your images. You build your figure. You export it. No installation, no account, no server, no data leaving your machine. I deliberately kept it as a single file because the last thing a stressed PhD student needs is a dependency to manage.

The core loop was simple: drop images into a panel grid, adjust each one independently, annotate directly on the canvas, apply a journal preset, and export. But the tool kept growing — not because I set out to build something big, but because every workflow it touched surfaced another problem worth solving.

Version 3.1 adds things I did not plan but probably should have from the start. A freeform canvas mode — so figures that do not fit a grid (posters, graphical abstracts, multi-part schematics) have a home. A pre-use crop editor that intercepts every image before it enters the canvas, so you are never cropping the same thing twice in two different tools. A real quantification engine: ROI intensity, integrated density, line profiles, cell counting by threshold. A reproducibility log baked into every PNG export as metadata. And AI-generated scientific diagrams — type a prompt, get a BioRender-style cartoon, place it directly into your figure, background removed.

The ambition changed a little. It is not just a microscopy figure tool anymore. It is closer to what you would get if PowerPoint, ImageJ, and BioRender had a single-file offspring that cared about publication correctness.

On building tools as a scientist

There is a version of scientific training that treats tool-building as a distraction from real science. Get the data, analyze it, write it up, move on. And there is real wisdom in that: time spent building infrastructure is time not spent at the bench.

But there is another version — one I have come to believe more fully as my PhD has progressed — the act of building a tool forces you to understand a problem at a depth that using tools never does. When I wrote the scale bar rendering code, I had to think carefully about what "calibrated" actually means when you have cropped an image. The source pixel width after cropping is not the same as the original image width, and getting that wrong produces a scale bar that looks right but lies.

The act of building a tool forces you to understand a problem at a depth that using tools never does.

I am not claiming FigureLab is finished. It has gaps I know about and probably gaps I do not. But it is real, it runs, and it has already saved me more time than it took to build. That seems like the right bar for whether something was worth doing.

A note on how it was built

FigureLab was built collaboratively with Claude (Anthropic's AI). The ideas, the workflow design, the frustration that motivated it, the decisions about what to build — those are mine. Claude was the implementation partner: writing and debugging the canvas rendering code, the TIFF export logic, the annotation system, the scale bar math. Working this way let me turn a specific scientific frustration into a working tool faster than I could have alone, and I think it is worth being transparent about that.

Open it and start building

The interface should be self-explanatory. If it is not, that is a bug. Press ? for the full keyboard shortcut reference.

01

Open in your browser

Click the link above. No download, no account, no sign-up. Chrome recommended. Works entirely offline once loaded.

02

Crop when you want to

Images go straight into the figure. Crop them afterwards from Crop & Scale — non-destructively, so you can re-open and change any crop later, tilt it, or reset it. Prefer the old flow? Turn on "crop images as I import them".

03

Choose grid or freeform

Grid mode for standard panel figures. Freeform mode for posters, graphical abstracts, or anything that needs custom placement. Switch any time.

04

Adjust, annotate, generate

Per-panel brightness, contrast, gamma, LUTs. Draw arrows, rulers, insets, text boxes. Or generate a scientific diagram with AI and place it alongside your data.

05

Run the audit

Deep Figure Audit checks LUT consistency, exposure, missing scale bars, and font size. Exposure Analysis flags overexposed or clipped panels before a reviewer does.

06

Export with everything embedded

PNG, TIFF, SVG, PDF, JPEG, or WebP at your target DPI. Every PNG carries a full reproducibility log as tEXt metadata — readable in FIJI and ImageJ.

What's new in v3.17.0

Updated 27 September 2026. v3.17.0 was built by making real figures end to end — a western blot, a time-lapse, a multichannel row — and fixing every place the work stalled. Rows can now hug their panels, so a blot stack has no dead space and its lanes stay in register. FigureLab writes the image-processing paragraph for your Methods from what the figure records, shows the resolution each panel really prints at, merges separately exported channel files into one panel, repeats an annotation across panels, and exports LZW-compressed TIFF for PLOS. Straighten-then-crop works, typed headings survive a resize, and the submission package describes only the panels the figure draws. 540 tests.

🧹

Quieter first run, fewer walls of buttons

Measured with a scripted audit rather than guessed: an empty figure no longer shows inert panel tools, the icon browser shows a few per group with a “show all”, the command palette box is the width it was meant to be, and 40 inputs a screen reader announced as unlabelled now have names.

🧬

The duplication screen journals run — run first

Beyond whole panels: a lane cloned inside a blot, a region of one micrograph reappearing in another — shifted, rotated or mirrored — is found by content-anchored patch matching and shown boxed, side by side. Flat background is excluded and the report says so. It finds candidates; it does not judge them.

🎨

Generate figures with your Gemini account

Write a prompt and FigureLab copies it and opens gemini.google.com — you generate there, free on your own account, and paste the image back as a tagged AI schematic. FigureLab transmits nothing: there is no in-app Google login because none exists that would not risk your account, and the release notes explain exactly why.

✨

AI edits schematics — never your data

AI-generated and hand-drawn objects can be edited, varied and style-matched. Imported experimental images and data panels are refused, loudly: journals treat AI alteration of research images as misconduct. A test asserts refused paths make zero network requests. Exporting AI content under a Nature, Science or Cell preset stops and writes the disclosure the journal requires.

🧬

169 icons, none of them owed anything

The library doubled with artwork imported from Bioicons under CC0 and MIT only — no attribution line, no publication licence, no watermark, no per-figure fee. Share-alike and software logos were excluded on purpose, every icon carries its licence record, and ⚖ Credits writes the attribution paragraph for anything that ever needs one.

⚖

Figures that look authored, not assembled

Homogenize collapses every drifted font, text size, stroke width and line colour to one value in a single undo step. Linked insets stay bound to their parent panel by id, so an adjusted parent updates its magnified inset instead of silently diverging. The submission package now carries a per-panel processing history, honest about being unsigned.

⟲

Tilted crops

Specimens rarely sit square to the camera. Drag the grip above the crop box to turn it, or type an angle — the region tilts and the panel comes out upright, instead of forcing a choice between a skewed panel and background wedges in the corners. It says plainly that a tilt resamples the display, and measurements still read the original samples, mapped back through the rotation.

⊞

Multi-crop, with editable regions

Cut several regions from one image, name each as you go, and get a named panel from each — six plates × three phage regions is eighteen panels that need no decoding afterwards. Every region shares one size so the panels stay uniform, while each keeps its own tilt. Click any banked region to reopen, move, tilt or rename it.

👁

Show a subset of your panels

Hide panels instead of deleting them: they leave the figure and the grid closes up, but stay in the panel list, the session file, and every adjustment you made. Lettering runs over visible panels only, so a subset reads A, B, C, D with no gaps. Deleting is a separate, explicit action.

⌐

Group bands & brackets

The outer level of labelling a dose series needs — "No ATC" and "+5 µM ATC" spanning three rows each, with a bracket. Build them by range, in repeating blocks of N, or from the panels' own group tags; they run down rows or across columns, and the bracket can be a solid bar, a square bracket, or nothing.

⇲

No wasted white space

A square grid cell holding a 4:3 photo wastes about a quarter of itself to letterboxing. Fit panels to images reshapes the cell to the content, holding the figure's overall width — the number a journal specifies — fixed. Tighten spacing closes gutters and margins in one action, and row/column headers can now sit right against the figure.

🧭

A sidebar organised by what you're doing

Images → Arrange → Crop & Scale → Annotate & Draw → Look → Measure → Check → Export. The old Simple/Advanced switch is gone: it hid about thirty-five controls, including whole tools like Batch Crop, which made them impossible to discover. Nothing is hidden now, and tools that can't work in your current layout mode say why.

🔬

Measurements read the real samples

16-bit and floating-point TIFF imports keep their native samples, so intensity is reported at the acquisition bit depth rather than the 8-bit display — and every result says which pixels produced it, including when it has to fall back. Saturation is reported at the sensor, not inferred from the screen.

🔤

PDFs carry real text

Panel letters, axis labels, titles and scale-bar text are laid down as genuine PDF text operators over the image — selectable, searchable, and sharp at any zoom — instead of being baked into the raster. Anything the base-14 fonts can't represent stays in the raster rather than being mangled.

🧬

Gene maps & genetic circuits

Base-pair-scaled maps in SBOL Visual notation, linear or circular, built from a pasted table, drawn from scratch, or imported from GenBank/FASTA. Features scale to real coordinates, so the drawing matches the sequence.

🧾

Printed size, not just pixels

Set the width your figure will be printed at — single column, 1.5 column, double — and see the physical size and the true DPI you'll get before exporting, rather than discovering it at submission.

🧬

Duplicate-panel check

Compares the pixels of every pair of panels, including rotated and mirrored reuse, and flags near-identical ones — before a journal's screening software does.

📖

Citable, with a DOI

Every release is archived on Zenodo with its own version DOI, and the repository ships a CITATION.cff so GitHub's "Cite this repository" button gives ready-made APA and BibTeX. The concept DOI always resolves to the latest version.

Request a feature — or ask anything

FigureLab is built from real workflow frustrations. If there's something you keep wishing it could do, or something that doesn't work the way you expect, I want to know. This is a one-person project built in public — your input shapes what gets built next.

✨

Request a feature

Open a GitHub issue with your idea. Describe the workflow problem you're hitting — not just the feature — and I'll figure out the best way to solve it.

Open on GitHub →

🐛

Report a bug

Something broke or behaved unexpectedly? File a bug report with what you did and what happened. Include your browser and OS if you can.

Open on GitHub →

💬

Ask a question

Not sure how something works? Can't find a feature? Ask in GitHub Discussions — questions are welcome, and the answer might become a tooltip or a doc page.

Open Discussions →

🗳️

What's on the roadmap?

Recent releases shipped drag-to-space spacing, on-image text, true high-resolution export, and universal undo. Vote for what comes next in GitHub Discussions.

Open Discussions →

A note on what gets built: Features that solve a workflow problem real scientists hit — and that fit the "single HTML file, no server, no account" constraint — are most likely to land. Features that require a backend, a database, or user accounts are off the table by design. The constraint is a feature, not a limitation.

Built with passion for science and discovery. You can just build things.

Ready to build your figure?

Free, open-source, and it runs entirely in your browser. Nothing to install.

Open FigureLab → GitHub