ESC/POS Commands

ESC/POS is a thermal printer command set developed by Epson. It is the industry standard for POS printers and offers the best compatibility.

Overview

Like ESC, ESC/POS uses binary control commands. Its broad industry adoption makes it the preferred choice for receipt printing.

Comparison with ESC

Feature	ESC	ESC/POS
Command format	Binary	Binary
Industry standard	No	✅ Epson standard
Compatibility	Average	Excellent
Primary use	Portable printers	Point-of-sale systems

Character encoding

Chinese text encoding

Because of printer hardware limitations, Chinese text must use GBK encoding. The SDK handles conversion automatically.

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Printer control commands

Initialize the printer (ESC @)

Initialize the printer, clear the print buffer, and restore default settings.

ESC @
Hex: 1B 40

Recommendation

Initialize the printer before each print job to ensure a known state.

Print and line feed (LF)

Print the buffer contents and advance to the next line.

LF
Hex: 0A

Print and carriage return (CR)

Print the buffer contents and return the carriage.

CR
Hex: 0D

Feed paper (ESC J)

Feed the paper forward by n units.

ESC J n
Hex: 1B 4A n

Parameter	Range	Description
n	0-255	Feed distance in dots

Feed n lines (ESC d)

Feed the paper forward by n lines.

ESC d n
Hex: 1B 64 n

Parameter	Range	Description
n	0-255	Number of lines to feed

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Text formatting commands

Set character size (GS !)

Set the character width and height multipliers.

GS ! n
Hex: 1D 21 n

Bit settings for parameter n:

• Bits 0–2: Horizontal multiplier (0–7 represents 1–8 times)
• Bits 4–6: Vertical multiplier (0–7 represents 1–8 times)

n value	Effect
0x00	Normal size (1x1)
0x10	Double height (1x2)
0x01	Double width (2x1)
0x11	Double width and height (2x2)
0x22	Triple width and height (3x3)
0x77	8× width and height (8x8)

Example:

1D 21 11    // Set width and height multipliers

Set alignment (ESC a)

Set text alignment.

ESC a n
Hex: 1B 61 n

n value	Alignment
0	Left aligned
1	Centered
2	Right aligned

Example:

1B 61 01    // Center aligned

Set bold (ESC E)

Enable or disable bold mode.

ESC E n
Hex: 1B 45 n

n value	Effect
0	Disable bold
1	Enable bold

Set underline (ESC -)

Set underline mode.

ESC - n
Hex: 1B 2D n

n value	Effect
0	Disable underline
1	1-dot underline
2	2-dot underline

Set reverse printing (GS B)

Set black/white reverse printing mode.

GS B n
Hex: 1D 42 n

n value	Effect
0	Disable reverse printing
1	Enable reverse printing

Set font (ESC M)

Select the font type.

ESC M n
Hex: 1B 4D n

n value	Font
0	Font A (12x24)
1	Font B (9x17)

Set line spacing (ESC 3)

Set the line spacing.

ESC 3 n
Hex: 1B 33 n

Parameter	Description
n	Line spacing (dots)

Restore default line spacing (ESC 2)

Restore the default line spacing.

ESC 2
Hex: 1B 32

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Barcode printing commands

Set barcode height (GS h)

Set the barcode height.

GS h n
Hex: 1D 68 n

Parameter	Range	Description
n	1-255	Barcode height (dots)

Example:

1D 68 50    // Set barcode height to 80 Dots

Set barcode width (GS w)

Set the barcode width.

GS w n
Hex: 1D 77 n

Parameter	Range	Description
n	2-6	Barcode width multiplier

Set HRI character position (GS H)

Set the printing position of human-readable interpretation (HRI) characters for the barcode.

GS H n
Hex: 1D 48 n

n value	Position
0	Do not print
1	Above barcode
2	Below barcode
3	Above and below

Print a barcode (GS k)

Print a one-dimensional barcode.

GS k m n [Data]
Hex: 1D 6B m n [Data]

Parameter	Description
m	Barcode type
n	Data length

Barcode type

m value	Barcode type	Data requirements
0	UPC-A	11-12 digits
1	UPC-E	6-8 digits
2	EAN-13	12-13 digits
3	EAN-8	7-8 digits
4	CODE39	Alphanumeric
5	ITF	Even number of digits
6	CODABAR	Digits + A-D
65	UPC-A	11-12 digits
66	UPC-E	6-8 digits
67	EAN-13	12-13 digits
68	EAN-8	7-8 digits
69	CODE39	Alphanumeric
70	ITF	Even number of digits
71	CODABAR	Digits + A-D
72	CODE93	ASCII
73	CODE128	ASCII (recommended)

Example:

1D 68 60          // Set barcode height 96
1D 77 03          // Set barcode width 3
1D 48 02          // HRI Print below
1D 6B 49 0D 7B 42 31 32 33 34 35 36 37 38 39 30 31 32 33
                  // Print CODE128 Barcode "1234567890123"

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QR code printing commands

QR code printing steps

QR code printing requires several commands in sequence:

1. Set cell size (GS ( k)

GS ( k pL pH cn fn n
Hex: 1D 28 6B 03 00 31 43 n

Parameter	Range	Description
n	1-16	Cell size (dots)

2. Set error correction level (GS ( k)

GS ( k pL pH cn fn n
Hex: 1D 28 6B 03 00 31 45 n

n value	Error correction level	Error correction capacity
48 (0x30)	L	7%
49 (0x31)	M	15%
50 (0x32)	Q	25%
51 (0x33)	H	30%

3. Store data (GS ( k)

GS ( k pL pH cn fn m [Data]
Hex: 1D 28 6B pL pH 31 50 30 [Data]

Parameter	Description
pL pH	Data length + 3 (low byte, high byte)
Data	QR code content

4. Print (GS ( k)

GS ( k pL pH cn fn m
Hex: 1D 28 6B 03 00 31 51 30

Complete example:

1D 28 6B 03 00 31 43 06                          // Set cell size to 6
1D 28 6B 03 00 31 45 31                          // Set error correction level to M
1D 28 6B 13 00 31 50 30 68 74 74 70 73 3A 2F 2F 65 78 61 6D 70 6C 65 2E 63 6F 6D
                                                  // Store data "https://example.com"
1D 28 6B 03 00 31 51 30                          // Print a QR code

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Paper cutting commands

Full cut (GS V)

Perform a full cut.

GS V m
Hex: 1D 56 m

m value	Effect
0	Full cut
1	Partial cut

Feed and cut (GS V)

Feed n lines and then cut the paper.

GS V m n
Hex: 1D 56 m n

m value	Effect
65 (0x41)	Feed n lines, then full cut
66 (0x42)	Feed n lines, then partial cut

Example:

1D 56 42 03    // Feed paper 3 Lines, then cut

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Image printing commands

Print a raster bitmap (GS v 0)

Print a raster bitmap image.

GS v 0 m xL xH yL yH [Data]
Hex: 1D 76 30 m xL xH yL yH [Data]

Parameter	Description
m	Print mode (0=Normal, 1=Double width, 2=Double height, 3=Double width and height)
xL xH	Horizontal byte count (Width/8)
yL yH	Vertical dot count (Height)
Data	Bitmap data

SDK processing

The SDK handles image binarization and data conversion automatically. Pass in the original image.

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Cash drawer commands

Open the cash drawer (ESC p)

Open the cash drawer.

ESC p m t1 t2
Hex: 1B 70 m t1 t2

Parameter	Description
m	Cash drawer pin (0 or 1)
t1	On time (t1 × 2ms)
t2	Off time (t2 × 2ms)

Example:

1B 70 00 19 FA    // Open the cash drawer

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Status query commands

Query printer status (DLE EOT)

Query printer status in real time.

DLE EOT n
Hex: 10 04 n

n value	Query target
1	Printer status
2	Offline status
3	Error status
4	Paper status

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Complete receipt example

Example command sequence

1B 40                       // Initialize the printer

// Print title
1B 61 01                    // Centered
1D 21 11                    // Double width and height
[GBK: XX Convenience store]
0A

// Print subtitle
1D 21 00                    // Restore normal size
[GBK: Order number: 20240115001]
0A
[GBK: ================================]
0A

// Print product list
1B 61 00                    // Left aligned
[GBK: Cola 500ml    x2    ￥6.00]
0A
[GBK: Potato chips Large pack     x1    ￥8.50]
0A
[GBK: Mineral water        x3    ￥4.50]
0A
[GBK: --------------------------------]
0A

// Print total
1D 21 10                    // Double height
1B 45 01                    // Bold
[GBK: Total: ￥19.00]
1B 45 00                    // Disable bold
1D 21 00                    // Restore normal mode
0A 0A

// Print a QR code
1B 61 01                    // Centered
1D 28 6B 03 00 31 43 05     // QR code cell size
1D 28 6B 03 00 31 45 31     // Error correction level M
1D 28 6B ... 31 50 30 [URLData]  // Store data
1D 28 6B 03 00 31 51 30     // Print a QR code
[GBK: Scan to follow the store]
0A

// Print a barcode
1D 68 50                    // Barcode height
1D 77 02                    // Barcode width
1D 48 02                    // HRI Position
1D 6B 49 ... [Barcode data]     // Print a barcode

// Feed and cut
1B 64 03                    // Feed paper 3 Lines
1D 56 42 00                 // Cut paper

Receipt structure

┌─────────────────────────────┐
│        XX Convenience store             │  ← Centered, Double width and height
│    Order number: 20240115001      │  ← Centered, Normal size
│ ════════════════════════════│
│ Cola 500ml    x2    ￥6.00  │  ← Left aligned
│ Potato chips Large pack     x1    ￥8.50  │
│ Mineral water        x3    ￥4.50  │
│ ────────────────────────────│
│ Total: ￥19.00               │  ← Double height, Bold
│                             │
│        [QR code]             │  ← Centered
│      Scan to follow the store           │
│                             │
│     |||||||||||||||         │  ← Barcode
│     6901234567890           │
└─────────────────────────────┘

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SDK integration

For ESC/POS usage in each language, see:

• Dart SDK - Cross-platform Flutter development
• Java SDK - Native Android development
• JavaScript SDK - Mini Program development
• OpenHarmony SDK - HarmonyOS / OpenHarmony applications
• Objective-C SDK - Native iOS development
• Swift SDK - iOS/macOS development

References

Complete ESC/POS command reference (PDF)