diff --git a/src/gmio_core/text_format.h b/src/gmio_core/text_format.h
new file mode 100644
index 0000000..6ed90c6
--- /dev/null
+++ b/src/gmio_core/text_format.h
@@ -0,0 +1,43 @@
+/****************************************************************************
+** GeomIO Library
+** Copyright FougSys (2 Mar. 2015)
+** contact@fougsys.fr
+**
+** This software is a reusable library whose purpose is to provide complete
+** I/O support for various CAD file formats (eg. STL)
+**
+** This software is governed by the CeCILL-B license under French law and
+** abiding by the rules of distribution of free software.  You can  use,
+** modify and/ or redistribute the software under the terms of the CeCILL-B
+** license as circulated by CEA, CNRS and INRIA at the following URL
+** "http://www.cecill.info/licences/Licence_CeCILL-B_V1-en.html".
+****************************************************************************/
+
+/*! \file text_format.h
+ *  Formats for textual representation
+ */
+
+#ifndef GMIO_TEXT_FORMAT_H
+#define GMIO_TEXT_FORMAT_H
+
+#include "global.h"
+
+/*! This enum defines the various formats to textually represent a float */
+enum gmio_float_text_format
+{
+    /*! Decimal floating point, lowercase (ex: 392.65) */
+    GMIO_FLOAT_TEXT_FORMAT_DECIMAL_LOWERCASE = 0,
+    /*! Decimal floating point, uppercase (ex: 392.65) */
+    GMIO_FLOAT_TEXT_FORMAT_DECIMAL_UPPERCASE,
+    /*! Scientific notation, lowercase (ex: 3.9265e+2) */
+    GMIO_FLOAT_TEXT_FORMAT_SCIENTIFIC_LOWERCASE,
+    /*! Scientific notation, uppercase (ex: 3.9265E+2) */
+    GMIO_FLOAT_TEXT_FORMAT_SCIENTIFIC_UPPERCASE,
+    /*! Use the shortest representation: decimal or scientific lowercase */
+    GMIO_FLOAT_TEXT_FORMAT_SHORTEST_LOWERCASE,
+    /*! Use the shortest representation: decimal or scientific uppercase */
+    GMIO_FLOAT_TEXT_FORMAT_SHORTEST_UPPERCASE
+};
+typedef enum gmio_float_text_format gmio_float_text_format_t;
+
+#endif /* GMIO_TEXT_FORMAT_H */
diff --git a/src/gmio_stl/internal/stla_write.c b/src/gmio_stl/internal/stla_write.c
index 5d91071..59060d1 100644
--- a/src/gmio_stl/internal/stla_write.c
+++ b/src/gmio_stl/internal/stla_write.c
@@ -83,14 +83,30 @@ GMIO_INLINE char* gmio_write_nspaces(char* buffer, int n)
     return buffer + offset;
 }
 
-GMIO_INLINE char* gmio_write_stdio_format(char* buffer, uint8_t prec)
+GMIO_INLINE char gmio_float_text_format_to_specifier(
+        gmio_float_text_format_t format)
+{
+    switch (format) {
+    case GMIO_FLOAT_TEXT_FORMAT_DECIMAL_LOWERCASE: return 'f';
+    case GMIO_FLOAT_TEXT_FORMAT_DECIMAL_UPPERCASE: return 'F';
+    case GMIO_FLOAT_TEXT_FORMAT_SCIENTIFIC_LOWERCASE: return 'e';
+    case GMIO_FLOAT_TEXT_FORMAT_SCIENTIFIC_UPPERCASE: return 'E';
+    case GMIO_FLOAT_TEXT_FORMAT_SHORTEST_LOWERCASE: return 'g';
+    case GMIO_FLOAT_TEXT_FORMAT_SHORTEST_UPPERCASE: return 'G';
+    }
+    /* Default, should not be here */
+    return GMIO_FLOAT_TEXT_FORMAT_DECIMAL_LOWERCASE;
+}
+
+GMIO_INLINE char* gmio_write_stdio_format(
+        char* buffer, char format_specifier, uint8_t prec)
 {
     int prec_len = 0;
 
     buffer[0] = '%';
     buffer[1] = '.';
     prec_len = sprintf(buffer + 2, "%u", prec);
-    buffer[2 + prec_len] = 'E';
+    buffer[2 + prec_len] = format_specifier;
     return buffer + 3 + prec_len;
 }
 
@@ -115,6 +131,7 @@ int gmio_stla_write(
         const gmio_stl_mesh_t* mesh,
         /* Options */
         const char* solid_name,
+        gmio_float_text_format_t float32_format,
         uint8_t float32_prec)
 {
     /* Constants */
@@ -141,12 +158,14 @@ int gmio_stla_write(
         return GMIO_ERROR_INVALID_BUFFER_SIZE;
 
     { /* Create XYZ coords format string (for normal and vertex coords) */
+        const char float32_specifier =
+                gmio_float_text_format_to_specifier(float32_format);
         char* it = coords_format;
-        it = gmio_write_stdio_format(it, float32_prec);
+        it = gmio_write_stdio_format(it, float32_specifier, float32_prec);
         it = gmio_write_nspaces(it, 2);
-        it = gmio_write_stdio_format(it, float32_prec);
+        it = gmio_write_stdio_format(it, float32_specifier, float32_prec);
         it = gmio_write_nspaces(it, 2);
-        it = gmio_write_stdio_format(it, float32_prec);
+        it = gmio_write_stdio_format(it, float32_specifier, float32_prec);
         *it = 0; /* Write terminating null byte */
         /* TODO: check the "format" string can contain the given precision */
     }
diff --git a/src/gmio_stl/internal/stla_write.h b/src/gmio_stl/internal/stla_write.h
index 3eb0a37..b81c354 100644
--- a/src/gmio_stl/internal/stla_write.h
+++ b/src/gmio_stl/internal/stla_write.h
@@ -17,6 +17,7 @@
 #define GMIO_INTERNAL_STLA_WRITE_H
 
 #include "../stl_mesh.h"
+#include "../../gmio_core/text_format.h"
 #include "../../gmio_core/transfer.h"
 
 /*! Writes geometry in the STL ascii format
@@ -30,6 +31,7 @@ int gmio_stla_write(
         const gmio_stl_mesh_t* mesh,
         /* Options */
         const char* solid_name,
+        gmio_float_text_format_t float32_format,
         uint8_t float32_prec);
 
 #endif /* GMIO_INTERNAL_STLA_WRITE_H */
diff --git a/src/gmio_stl/stl_io.c b/src/gmio_stl/stl_io.c
index 077143f..c6809ef 100644
--- a/src/gmio_stl/stl_io.c
+++ b/src/gmio_stl/stl_io.c
@@ -127,9 +127,13 @@ int gmio_stl_write(
         case GMIO_STL_FORMAT_ASCII: {
             const char* solid_name =
                     options != NULL ? options->stla_solid_name : NULL;
-            const uint8_t float32_prec =
+            const gmio_float_text_format_t float_fmt =
+                    options != NULL ? options->stla_float32_format :
+                                      GMIO_FLOAT_TEXT_FORMAT_DECIMAL_LOWERCASE;
+            const uint8_t float_prec =
                     options != NULL ? options->stla_float32_prec : 9;
-            error = gmio_stla_write(trsf, mesh, solid_name, float32_prec);
+            error = gmio_stla_write(
+                        trsf, mesh, solid_name, float_fmt, float_prec);
             break;
         }
         case GMIO_STL_FORMAT_BINARY_BE: {
diff --git a/src/gmio_stl/stl_io_options.h b/src/gmio_stl/stl_io_options.h
index 7042b0a..e1b1316 100644
--- a/src/gmio_stl/stl_io_options.h
+++ b/src/gmio_stl/stl_io_options.h
@@ -22,6 +22,7 @@
 
 #include "stl_global.h"
 #include "../gmio_core/endian.h"
+#include "../gmio_core/text_format.h"
 
 /*! Options for gmio_stl_write() */
 struct gmio_stl_write_options
@@ -36,6 +37,15 @@ struct gmio_stl_write_options
      */
     const char* stla_solid_name;
 
+    /*! The format used when writting float values as strings
+     *
+     *  Option useful only with STL ascii format (GMIO_STL_FORMAT_ASCII).
+     *
+     *  Defaulted to \c GMIO_FLOAT_TEXT_FORMAT_DECIMAL_LOWERCASE when calling
+     *  gmio_stl_write() with \c options==NULL
+     */
+    gmio_float_text_format_t stla_float32_format;
+
     /*! The maximum number of significant digits when writting float values
      *
      *  Option useful only with STL ascii format (GMIO_STL_FORMAT_ASCII).