How do I make a P&ID diagram?

List your process equipment with tag numbers, describe how they connect via pipes, name the instruments at each measurement point, and define the control loops. Paste that description into Figviz, choose a style and aspect ratio, and generate. Refine the prompt to add detail such as safety relief valves, bypass lines, or additional instrumentation.

Is the P&ID diagram maker free?

Yes. You can generate P&ID diagrams using the free credits every Figviz account starts with. Purchasing any pay-as-you-go credit pack removes the watermark and unlocks higher resolutions up to 4K. Credits never expire.

What is the difference between a P&ID and a PFD?

A process flow diagram (PFD) shows the overall process flow and major equipment at a high level, with approximate flow rates and temperatures. A P&ID goes further and shows every pipe, valve, instrument, and control loop in the plant, using standard ISA symbols and tag numbers. P&IDs are the primary reference for construction, operations, and safety reviews.

What are instrument bubbles in a P&ID?

Instrument bubbles are the circles used in P&IDs to represent measurement and control devices. The letters inside the circle identify the variable being measured (F for flow, P for pressure, L for level, T for temperature) and the function of the device (T for transmitter, C for controller, I for indicator). A bubble with a horizontal line through it means the instrument is located in a control room or DCS panel rather than in the field.

Can I use P&ID diagrams for engineering documentation?

Yes. Figviz exports high-resolution PNG files up to 4K that are suitable for engineering reports, design review packages, training materials, and presentations. As an AI-generated tool the diagrams are ideal for concept-level and educational work. For legally binding or construction-issue drawings, the output should be reviewed and formally stamped by a licensed engineer. Diagrams from a paid account are yours to use in your own engineering documents.

AI-Powered

P&ID Diagram Maker P&ID Diagrams

Describe a process and get a publication-ready piping and instrumentation diagram in seconds, complete with ISA instrument bubbles, control loops, pipe labels, and equipment tags. No CAD software required.

Last updated: 2026-06-21

✓Standard ISA symbols✓Instrument bubbles and tags✓Control loops and signals✓Export-ready at 4K

P&ID Diagram Maker

Style

Describe your process

Free to try ·

Not what you expected? Tell us

Preview

Your P&ID diagram will appear here

Describe your process and click Generate

P&ID Diagram Examples

Browse P&ID diagrams made with Figviz, or generate your own above

View

Basic Pump, Tank, and Valves P&ID

A foundational P&ID with a centrifugal pump, storage tank, isolation valves, and a flow control loop.

pumptankvalve

Heat Exchanger P&ID

Shell-and-tube heat exchanger P&ID with a temperature transmitter, temperature controller, and bypass control valve.

heat exchangertemperature controlbypass

Distillation Column P&ID

Distillation column P&ID including reboiler, overhead condenser, reflux drum, and multiple control loops.

distillationcolumnreboiler

P&ID with Instrument Bubbles and Control Loops

A detailed P&ID focused on instrument bubble notation, signal line types, and a cascade control strategy.

instrument bubblescontrol loopscascade

Water Treatment Process P&ID

Water treatment P&ID covering coagulation, filtration, and chlorine dosing with flow and level instrumentation.

water treatmentfiltrationdosing

Labeled P&ID with Standard ISA Symbols

A reference-style P&ID with annotated ISA symbols for valves, transmitters, controllers, and piping.

ISA symbolsreferencelabeled

What is a P&ID diagram maker?

A P&ID diagram maker is a tool that lets you create piping and instrumentation diagrams without drafting software. A P&ID (piping and instrumentation diagram) is an engineering drawing that shows the physical sequence of equipment, pipes, and instrumentation in a process plant, along with the control loops that govern how the plant operates. Figviz generates these diagrams from a plain-language description, placing ISA-standard instrument bubbles, valve symbols, and pipe connections automatically so engineers, students, and process designers can produce clear P&IDs in seconds.

How to make a P&ID diagram

List the main process equipment: pumps, tanks, heat exchangers, columns, and vessels with their tag numbers (e.g. P-101, TK-201).

Describe the pipe connections: which streams enter and leave each piece of equipment and in what sequence.

Specify the instrumentation: identify each measurement point (flow, pressure, level, temperature) and give each instrument a tag such as FT-101 or TT-201.

Define the control loops: state which controller reads which transmitter and which control valve it drives.

Choose a style (Classic, Colorful, or Minimal) and aspect ratio, then generate.

Review the output and refine the prompt to add safety valves, bypass lines, or additional detail.

Common P&ID symbols and instrument tags

Equipment symbols: centrifugal pump (circle with triangle), shell-and-tube heat exchanger (rectangle with tubes), vessel or tank (tall rectangle), column (tall rectangle with internals).

Valve symbols: gate valve (bow-tie), globe valve (circle on stem), check valve (angled flap), control valve (bow-tie with actuator circle on top).

Instrument bubbles: a circle with a two-letter prefix identifies the measured variable (F = flow, P = pressure, L = level, T = temperature) and the function (T = transmitter, C = controller, I = indicator, V = valve).

Signal lines: a solid line is a process pipe; a dashed line is a pneumatic or electrical signal; a double-dashed line is a digital or data highway signal.

Tag numbering: the loop number typically identifies the unit area and a sequential number, for example FT-101 is the first flow transmitter in Unit 100.

Tips for a clear and accurate P&ID

Always assign a tag number to each piece of equipment and instrument before generating, as consistent numbering produces a diagram that reads like a real engineering document. List the control strategy explicitly, for example "FC-201 reads FT-201 and throttles FV-201," so the AI places the correct signal lines. For complex systems, generate individual sections (feed section, reaction section, separation section) and combine them. Use the Classic style for formal engineering reviews and Colorful for presentations or training materials. After downloading, verify that all instrument bubbles show the correct letter codes and that no pipe connections are missing before sharing with colleagues.

Frequently asked questions

A P&ID diagram maker is a tool that generates piping and instrumentation diagrams from a description of your process. With Figviz you describe the equipment, pipes, instruments, and control loops in plain language and get a clean diagram with standard ISA symbols and instrument bubbles, without needing CAD or specialist drafting software.

Related engineering tools

All tools →

Make your own p&id diagram with Figviz

Create a free account and get starter credits to generate your own. No credit card required.