Technological advancements have fundamentally transformed the face of human life, particularly in shaping the consumption patterns of Generation Z those born between 1997 and 2012 who came of age in a deeply digital landscape. The expansion of internet access has elevated social media far beyond its original function as a communication tool. In the contemporary era, these platforms serve as vital arenas for fostering social engagement, forming the foundation of public discourse, and shaping consumer preferences. As highlighted by Ashrafuzzaman et al. (2022), social media has transcended its role as a hub for information exchange to become a critical ecosystem that actively builds social bonds, shapes public sentiment, and exerts a profound influence on modern consumer decision-making processes.
TikTok has emerged as one of the most dominant and popular social media platforms, particularly among younger generations. As of April 2023, Indonesia ranked second globally, with over 113 million TikTok users, following the United States (Putri & Hayu, 2024). Beyond serving as an entertainment platform, TikTok also functions as a digital business hub, where users can discover product information, interact, and even make purchases through features such as TikTok Shop and affiliate programs. The increasing use of TikTok is closely related to the For You Page (FYP) algorithm, which is the main driving force because it can tailor content to users’ interests, thereby providing a more personalized experience than other platforms (Bhandari & Bimo, 2022). This unique aspect of TikTok makes it a major influence on the consumption behavior of the younger generation. Previous research has confirmed that the presence of marketing content and consumer reviews on TikTok can significantly increase purchase intention. In fact, TikTok content can drive consumers to purchase certain products by more than 50% (Pratama et al., 2023). Another study found that creative content and live streaming features on TikTok are highly effective at capturing consumer attention, increasing engagement, and boosting purchase intent among Gen Z. Short-form video and live streaming formats have proven to be more effective at building trust and engagement than traditional promotional methods (Poh et al., 2024).
In the context of fashion, Hallyu plays a significant role in shaping the clothing styles of Indonesians. The spread of digital content and modern media has accelerated the expansion of Korean trends, ranging from oversized cuts, layering techniques, and pastel colors to the fusion of casual and modern styles, making them easily embraced in Indonesia (Wicaksono et al., 2021). Indonesia’s younger generation, particularly millennials and Gen Z, frequently emulate the styles of Korean artists, such as dresses, knitwear, and oversized outfits, because they are perceived as attractive, comfortable, and suitable for Indonesia’s tropical climate.
This aligns with Irdayanti et al. (2024), who confirmed that the Korean Wave positively influences Gen Z’s interest in fashion shopping. Korean casual style has become the most sought-after category, even reaching a market value of 8.31 trillion rupiah. These findings also indicate that the Korean Wave has a significant influence on Gen Z’s interest in online fashion shopping, particularly regarding casual wear, which is the primary choice of the younger generation of consumers. Thus, it can be concluded that exposure to Korean culture through K-Pop and K-Dramas not only shapes lifestyle preferences but also drives Gen Z’s consumer behavior toward the Korean fashion industry.
Furthermore, self-image or self-identity has a substantial impact on the consumer behavior of Generation Z, particularly in the context of fashion consumption and e-commerce. Individuals in this generation who possess a positive self-concept generally exhibit more discerning and cautious purchasing behavior, as they do not feel compelled to express their identity through material possessions. Conversely, those with a negative self-concept are more prone to impulsive purchasing decisions, which are often driven by a desire to enhance their self-image and lifestyle by purchasing specific products (Yuniasanti & Nurwahyuni, 2023).
In marketing, brand image is a key factor that enhances the appeal of fashion products. By leveraging social media platforms, brands can build a strong brand perception through visual aesthetics, partnerships with influencers, and the delivery of emotionally resonant messages tailored to younger demographics. The synergistic effect of social media exposure and an appealing brand image can significantly impact consumer purchasing behavior. Ultimately, brand image encapsulates the identity and reputation of a product or service (Tamba & Melita, 2024), One of the main factors is that this style is considered better able to represent Generation Z’s self-identity. This style aligns with the image they wish to project in their social and digital lives. This is influenced by strong brand imagery and the role of social media platforms like TikTok, which significantly shape young consumers’ perceptions and preferences regarding fashion trends. Therefore, this study is important for analyzing the influence of TikTok, self-image, and brand image on Generation Z’s purchasing decisions regarding Korean-style fashion products, with the hope of contributing to digital marketing, specifically in designing branding strategies that are more relevant to the character and needs of today’s young consumers.
Previous studies have highlighted the importance of TikTok, brand image, and self-image as key factors influencing Generation Z’s fashion purchasing decisions. Social media communication, whether from companies or fellow users, can foster positive perceptions of local brands, as seen in the Erigo brand (Marklen et al., 2025). Arifin et al. (2024) and Kim and Cho (2023) further note that the Korean Wave phenomenon not only increases interest but also plays a role in shaping self-identity and fashion preferences among Genn Z.
Although extensive research has been conducted on social media, self-image, and brand image, a clear research gap remains. Previous studies on Korean fashion have generally focused on only two variables separately, thus failing to provide a comprehensive picture of TikTok, brand image, and self-image simultaneously within the context of Korean fashion among Generation Z at the local level, such as in the Kalapanunggal Subdistrict. This situation highlights the need for further research to deepen and enhance the practical application of our understanding of consumption patterns and the factors driving purchasing decisions related to Korean fashion among Generation Z.
This study is novel in that it combines three important variables, namely TikTok social media, self-image, and Brand Image, to examine their influence on fashion purchasing decisions. In addition, this study places the local context of Gen Z in Kalapanunggal as an object of study, thus providing a novel perspective.
This study is also urgent, given the rise of Korean-style fashion, the dominance of Gen Z as consumers of digital fashion, and the role of TikTok as the main platform in the formation of fashion trends. The results are expected to contribute to businesses, local brands, and online sellers in designing effective marketing strategies for the Gen Z segment.
Thus, this study is entitled: "The Influence of TikTok Social Media, Self-Image, and Brand Image on Korean Style Fashion Purchase Decisions among Gen Z in Kalapanunggal". The results of this study are expected to be a strategic consideration for fashion business actors, especially Korean-style fashion product providers, in designing marketing strategies through TikTok social media that are in harmony with the self-image and brand image of Gen Z consumers, so that they can improve purchasing decisions and business competitiveness sustainably.

This study employed a quantitative approach using an associative technique. This method was chosen to enable the precise, objective, and systematic analysis of the relationships between variables using statistical calculations. This study aimed to examine how the existing variables influence each other. According to Sugiyono (2023), associative research is used to determine the relationship between two or more variables. This study aims to determine the extent of the influence of the independent variables, TikTok, self-image, and brand image, on the dependent variable, which is the decision to purchase Korean-style fashion among Gen Z in Kalapanunggal.
This study was conducted in the Kalapanunggal Subdistrict, Sukabumi Regency. The study population consisted of Generation Z individuals aged 15–28 years who resided in the area, estimated to number approximately 11,967 people. As not everyone is an active TikTok user, the researcher opted for non-probability sampling, which involves selecting a sample based on specific considerations or criteria. Purposive sampling was used because the researcher aimed to select respondents with a relevant understanding of the issues under study. The number of respondents was determined using the Slovin formula to calculate the sample size. According to Santoso (2023), the Slovin formula is a method for calculating the sample size from a known population, taking into account a certain margin of error. Because the population size for this study was known, the researcher calculated the sample size using the Slovin formula. Based on this formula, the calculated sample size was 99 participants; however, the researcher chose to increase it to 100.
For the data collection phase, a closed-form survey instrument based on the Likert scaling technique was used and processed using SPSS software (version 31). The analytical sequence involved rigorous testing of the research instruments (validity and reliability) and verification of classical assumptions, including normality and variance consistency. T-tests for individual variables and F-tests for collective impact were utilized, alongside an assessment of the R-squared (R2) value to measure the model’s predictive accuracy.

3.1. Results

3.1.1. Validity Test
The Statistical Process for this study was carried out using SPSS 31, focusing on rigorous quantitative evaluation. The validity assessment for the 100 participants was based on a comparison between the observed r-values and standard R-table benchmarks. At a 5% margin of error, the research instrument achieved validity when the R-statistic exceeded the table requirements, and the significance level remained consistently below the 0.05 threshold. This verification process confirmed the reliability of the indicators used to capture the dynamics of the construction studied (see Table 1).

Table.1 Results of Tiktok Social Media Validity Test, Self-Image and Brand Image on Purchase Decisions

Source: Data processed using SPSS 31 (2025)

3.1.2. Reliability Test
The coefficient is used, following the methodological standards established by Ghozali (2018), and a construct is considered reliable and stable if the alpha coefficient (Alpha) exceeds the threshold of 0.70. These benchmarks ensure that the items used in the survey can provide consistent results when given repeatedly under the same conditions (see Table 2).

Table 2. Tiktok Social Media Reliability Test Results, Self Image, Brand Image and purchase decisions

An instrument is considered reliable if it produces a Cronbach's alpha score greater than 0.70. These figures show the reliability of the tools used in this study. Consequently, the Cronbach’s alpha value for each variable was greater than 0.70. It can be affirmed that all the variables in this study met the necessary criteria.

3.1.3. Normality Test
For more details, see Table 3.

Table 3. Kolmogorov-Smirnov Normality Test (One-Sample Kolmogorov-Smirnov Test)

Normality test results using a single sample of the Kolmogorov-Smirnov against residues that are not standardized Asimp values. Sig. (tail 2) of 0.101, which is greater than the significance level of 0.05. This shows that the residual data are normally distributed, so the assumption of normality in the regression model has been met.

3.1.4. Multicollinearity Test
This was carried out using a Tolerance Value of > 0.10 and VIF. For more details, see Table 4.

Table 4. Multicollinearity Test: VIF (Variance Inflation Factor) Values

Note: Dependent Variable: Purchase Decision (Y).

The multicollinearity test results showed that all independent variables, namely social media, self-image, and Brand Image, had tolerance values of 0.237, 0.204, and 0.245, respectively, which were all greater than 0.10. In addition, the Variance Inflation Factor (VIF) values for the three variables were 4,216, 4,901, and 4,079, which were still below the maximum limit of 10. Thus, it can be concluded that there is no multicollinearity between the independent variables in the regression model, so that each variable can explain the dependent variable of the purchase decision independently, and the regression model is suitable for further analysis.

3.1.5. Heteroscedasticity Test
Several indicators can be used to determine the heteroscedasticity of the model. In this construction, the researcher used a scatter plot graph by observing the scatter pattern divided between the sresid (residual studied) and ZPRED (standardized predictive value) variables (see Figure 1).

Figure 1. Scatterplot of the Heteroscedasticity test

Based on the results of the heteroscedasticity test using a scatterplot, it can be concluded that the regression model does not experience symptoms of heteroscedasticity. This is shown by the distribution pattern of residual points that spread randomly, both above and below the zero axis, and do not form certain patterns, such as cones, widens, or waves. This condition indicates that the residual variance was constant for all predictor values. Thus, the assumption of homoscedasticity is fulfilled, so the regression model is feasible for further analysis and hypothesis testing.

3.1.6. Multiple Linear Regression Test
The multiple linear regression model used in this study is as follows (see Table 5):

Table 5. Multiple Linear Regression Coefficients

Based on the results of the multiple linear regression analysis, the following regression equations were obtained:

Y= 6.990 + 0.399 X1 + 0.271 X2 + 0.446 X3

The derived regression model reveals a constant (intercept) of 6.990, signifying that in the absence of TikTok social media, self-image, and brand image, or if these factors are held at zero, the baseline value for Purchase Decisions remains at 6.990. Regarding the predictors, the Social Media coefficient of 0.399 suggests that each incremental unit of digital engagement corresponds to a 0.399 increase in consumer purchasing intent, provided that other variables remain static. Furthermore, the Self-Image coefficient of 0.271 indicates that a one-unit enhancement in personal identity perception yields a 0.271 rise in the dependent variable. Finally, the Brand Image coefficient of 0.446 demonstrates that every unit improvement in brand reputation boosts procurement choices by 0.446. Given that all coefficients are positive and statistically significant, TikTok social media, self-perception, and brand prestige serve as vital positive catalysts for the buying behavior of Generation Z.

3.1.7. t-Test (Partial)
For more details, see Table 6.

Table 6. Result of the t-test (Partial)

H1: tiktok social media has a positive and significant effect on purchasing decisions The results of the t test showed that the social media variables that have been calculated t value of 3,755 with a significance level of < 0.001, which is smaller than 0.05. This shows that social media has a positive and significant influence on purchasing decisions. Thus, H1 is accepted.
H2: Self-image positively and significantly influences purchasing decisions. Self-image variables obtained t value calculated at 2.090 with a significance value of 0.039 < 0.05. These results show that self-image has a positive and significant effect on purchase decisions. Therefore, H2 is accepted.
H3: Brand Image has a positive and significant influence on purchasing decisions. The test results showed that the Brand Image variable had a calculated t value of 3.892 with a significance level < 0.001, which is smaller than 0.05. This means that brand image has a positive and significant influence on purchase decisions. Thus, H3 is accepted.

3.1.8. F Test (Simultaneous)
For more details, see Table 7.

Table 7. F-test (Simultaneous) Results (ANOVA)

H4: Social Media, Self-Image, and Brand Image simultaneously have a positive and significant effect on Purchase Decisions
Regarding the collective influence of the independent constructs, the ANOVA (F-test) analysis produced a calculated value of 121.629. Because the probability value (p < 0.001) remains well within the highly significant range, it is evident that Social Media, Self-Image, and Brand Image work in tandem to determine consumer buying behavior. These findings validate the model's goodness-of-fit, confirming that the regression framework is statistically sound and that H4 is supported.

3.1.9. Coefficient of Determination Test (R2)
For more details, see Table 8.

Table 8. Results of the Coefficient of Determination Test (Model Summary)

The statistical results identified an R-squared value of 0.792, indicating a strong prediction for the proposed model. This indicates that approximately 79.2% of the factors influencing the choice of Generation Z’s mode of acquisition are explained by the combined impact of the independent variables studied. The remaining 20.8% of the variance was determined by extraneous variables not addressed in this study, suggesting that although the current model is very comprehensive, other fundamental elements still contribute to the final buying behavior.

3.2. Discussion

3.2.1. The Influence of TikTok Social Media on Purchase Decisions
Based on the results of the t-test, the TikTok social media variable has a calculated t value of 3.755 with a significance level < 0.001, which is smaller than 0.05. In addition, the regression coefficient indicates a positive direction. This shows that TikTok social media has a positive and significant effect on purchase decisions. Thus, the first hypothesis (H1) in this study, which states that "TikTok Social Media has a positive and significant effect on purchase decisions" is stated to be acceptable.

3.2.2. The Influence of Self Image on Purchase Decisions
According to the results of research in the Kalapanunggal District, based on the results of the t-test, self-image variables obtained with a calculated t value of 2.090 with a significance level of 0.039, which is smaller than 0.05. In addition, the regression coefficient indicates a positive direction. This shows that self-image has a positive and significant effect on purchase decisions. Thus, the second hypothesis (H2), which states that "self-image has a positive and significant effect on purchasing decisions" is accepted.

3.2.3. The Influence of Brand Image on Purchase Decisions
Based on the results of research in the Kalapanunggal district, t-test results, brand image variables obtained with a calculated t value of 3.892 with a significance level < 0.001, which is smaller than 0.05. In addition, the regression coefficient indicates a positive direction. This shows that Brand Image has a positive and significant effect on purchasing decisions. Thus, the third hypothesis (H3), which states that "Brand Image has a positive and significant effect on purchasing decisions" is accepted.

3.2.4. The Simultaneous Influence of TikTok Social Media, Self Image, and Brand Image on Purchase Decisions
Generation Z Consumers’ Purchase Decisions in Kalapanunggal Subdistrict Influenced by TikTok, Self-Image, and Brand Image. This conclusion is based on the results of a regression test, which yielded an F-value of 121.629 at a significance level of 0.001 < 0.05, and an R-squared value of 0.792 (79.2%). Consequently, it can be concluded that 79.2% of the variation in the purchase decision variable is explained by these three variables, while the remaining 20.8% is influenced by factors outside this study’s scope. This is (H4) in the present study.

Based on the results of the t-test and F-test in this study, all proposed hypotheses (H1–H4) were found to be significant. The t-test showed that each independent variable, namely TikTok Social Media, Self-Image, and Brand Image, had a positive and significant influence on purchasing decisions. Furthermore, the F-test results indicate that these three variables have a significant effect on consumer purchasing decisions. This relationship is reinforced by an R-squared value of 79.2%, indicating that the remaining 20.8% is influenced by variables outside the scope of this study. Thus, all hypotheses in this study are supported by the empirical data obtained, both partially and simultaneously.