OBD PID Utility

OBD-II PID Raw Data Decoder

Decode common OBD-II Mode 01 raw PID bytes into engineering values such as engine RPM, vehicle speed, coolant temperature, throttle position, fuel level, intake manifold pressure, timing advance, mass air flow and control-module voltage.

✓ Mode 01 ✓ RPM ✓ Speed ✓ Temperature ✓ Throttle ✓ MAF

PID

OBD-II Raw Data Decode

● Ready

Input Style Response mode expects the service response byte 0x41, followed by PID and raw data.

Speed / Temperature Display Raw OBD-II formulas are calculated first; optional converted units are shown separately.

PID Examples: 0x05 coolant temperature, 0x0C RPM, 0x0D vehicle speed.

Raw Data Bytes Enter only the PID data bytes in separate mode.

Scope: this page focuses on standardized OBD-II Mode 01 live-data PIDs and their published raw-byte formulas. Manufacturer-specific PIDs, enhanced diagnostics, UDS DIDs and proprietary scaling require the relevant vehicle or ECU documentation and are not guessed.

OBD-II PID Decode Result Decoded

Decoded Sensor Value —

PID —

PID Name —

Raw Data —

Required Bytes —

Decoded Value —

Unit —

Formula —

Byte A —

Byte B —

Byte C —

Byte D —

Input Length —

Calculation Breakdown

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What Is an OBD-II PID Raw Data Decoder?

An OBD-II PID Raw Data Decoder converts hexadecimal bytes returned by a vehicle’s OBD-II system into engineering values. In Mode 01, each Parameter ID identifies a current-data item such as engine speed, vehicle speed, temperature, throttle position or fuel level.

The response bytes themselves are usually not the final displayed value. Standardized equations define how raw bytes A, B, C and D must be scaled.

OBD-II Mode 01 Response Format

Request:
01 0C

01:
Mode 01 — Current Data

0C:
Engine RPM PID


Typical response application bytes:
41 0C 1A F8

41:
Positive response to Mode 01

0C:
PID

1A F8:
Raw data bytes A and B

Engine RPM PID 0x0C

Engine RPM uses two raw bytes. Byte A forms the high byte and B forms the low byte.

Formula:

RPM =
(256 × A + B) / 4


Example:

A = 0x1A = 26
B = 0xF8 = 248

256 × 26 + 248
= 6904

6904 / 4
= 1726 RPM

Vehicle Speed PID 0x0D

Vehicle speed is one of the simplest standard PIDs. Its single byte directly represents speed in kilometres per hour.

Raw:
64 hex

Decimal:
100

Vehicle Speed:
100 km/h

Approximate mph:
62.14 mph

Coolant Temperature PID 0x05

Formula:

Coolant Temperature °C =
A - 40


Example:

A = 0x7B
= 123 decimal

123 - 40
= 83°C

The same offset formula is also used by several standardized OBD-II temperature PIDs.

Throttle Position PID 0x11

Absolute throttle position uses one byte scaled to a percentage.

Throttle % =
A × 100 / 255

A = 0x80
= 128

Throttle =
128 × 100 / 255
≈ 50.196%

Mass Air Flow PID 0x10

The Mass Air Flow sensor PID uses two bytes and reports grams per second.

MAF =
(256 × A + B) / 100

Example:

A = 0x01
B = 0xF4

Raw 16-bit value =
500

MAF =
5.00 g/s

Common OBD-II Mode 01 PID Formulas

PID	Parameter	Bytes	Formula
0x04	Calculated Engine Load	1	A × 100 / 255 %
0x05	Engine Coolant Temperature	1	A − 40 °C
0x0A	Fuel Pressure	1	A × 3 kPa
0x0B	Intake Manifold Absolute Pressure	1	A kPa
0x0C	Engine RPM	2	(256A + B) / 4
0x0D	Vehicle Speed	1	A km/h
0x0E	Timing Advance	1	A / 2 − 64 degrees
0x0F	Intake Air Temperature	1	A − 40 °C
0x10	Mass Air Flow	2	(256A + B) / 100 g/s
0x11	Throttle Position	1	A × 100 / 255 %
0x2F	Fuel Tank Level Input	1	A × 100 / 255 %
0x33	Absolute Barometric Pressure	1	A kPa
0x42	Control Module Voltage	2	(256A + B) / 1000 V
0x46	Ambient Air Temperature	1	A − 40 °C
0x5C	Engine Oil Temperature	1	A − 40 °C

OBD-II PID vs UDS DID

An OBD-II PID and a UDS Data Identifier are not the same field. Standard OBD-II Mode 01 generally uses a one-byte PID, while UDS ReadDataByIdentifier uses two-byte DIDs.

OBD-II:
01 0C
→ Engine RPM PID 0x0C

UDS:
22 F1 90
→ ReadDataByIdentifier DID 0xF190

Manufacturer-Specific OBD Data

Vehicles can expose enhanced diagnostic parameters beyond the universally standardized OBD-II PID formulas. Their identifiers, scaling, offsets, byte order and units can vary by manufacturer, ECU and model.

This decoder therefore reports unsupported PIDs as unknown instead of applying a formula belonging to a different parameter.

OBD-II PID Raw Data Decoder FAQs

What is an OBD-II PID?

PID means Parameter ID. It identifies a particular diagnostic data parameter within an OBD-II service.

What does Mode 01 mean?

Mode 01 requests current powertrain diagnostic data such as RPM, speed, temperature and sensor values.

What is PID 0x0C?

PID 0x0C is engine RPM.

How is OBD-II RPM calculated?

Engine RPM equals (256 × A + B) divided by 4.

What is PID 0x0D?

PID 0x0D reports vehicle speed in kilometres per hour.

What is PID 0x05?

PID 0x05 is engine coolant temperature, calculated as A minus 40 degrees Celsius.

What does response byte 0x41 mean?

It is the positive response service byte corresponding to Mode 01.

Should I include CAN or ISO-TP headers?

No. Enter the OBD-II application bytes or use separate PID and raw-data mode. CAN identifiers and ISO-TP PCI bytes belong to lower transport layers.

Can every vehicle PID be decoded?

No. Manufacturer-specific and enhanced PIDs require the correct vehicle or ECU documentation.

Is PID 0xF190 a VIN PID?

No. F190 is a two-byte UDS Data Identifier, not a standard one-byte OBD-II Mode 01 PID.

Decode OBD-II Mode 01 Sensor Data

Convert standardized OBD-II raw PID bytes into RPM, speed, temperatures, percentages, pressure, airflow, voltage and other useful live-data values without guessing proprietary ECU formulas.